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Stock-Based Compensation

Note 5 - Stock-Based Compensation

Under the fair value recognition provisions of U.S. GAAP for accounting for stock-based compensation, the Company measures stock-based compensation expense at the grant date based on the fair value of the award and recognizes the compensation expense over the requisite service period, which is generally the vesting period.

The following table presents the classification of stock-based compensation expense recognized for the periods below:

	Three months ended September 30,					Nine months ended September 30,
(in thousands)	2018			2017		2018		2017
Selling, general and administrative expense	$	440		$	106	$	1,446	$	351
Research and development expense		(3	)		5		98		43
Total stock-based compensation expense	$	437		$	111	$	1,544	$	394

Note 7— Stock-Based Compensation

Stock Options and Restricted Stock Awards

The Company has various share-based compensation plans, including the Amended and Restated 2002 Stock Plan, the Third Amended and Restated 2017 Equity Incentive Plan, the 2013 Non-Employee Directors’ Equity Incentive Plan and the New-Hire Equity Incentive Plan (collectively, the “Plans”). The Plans are designed to assist in attracting, motivating and retaining employees and directors and to recognize the importance of employees to the long-term performance and success of the Company. The Company has also granted stock options to certain non-employees outside of the Plans.

The Company recognized share-based compensation expense related to grants of stock options, RSUs and common stock awards to employees, directors and consultants of $0.5 million, and $1.0 million during the years ended December 31, 2017 and 2016, respectively. The following table summarizes the stock-based compensation expense which was recognized in the consolidated statements of operations for the years ended December 31,

(Dollars in thousands)	2017		2016
Selling, general and administrative	$	452	$	630
Research and development		50		385
Total	$	502	$	1,015

The majority of the RSUs and options to purchase common stock vest on the anniversary of the date of grant, which ranges from one to four years. Share-based compensation expense related to these awards is recognized on a straight-line basis over the related vesting term in most cases, which generally is the service period. It is the Company’s policy to issue new shares upon the exercise of options.

Stock Options: The following is a summary of the Plans’ stock option activity during the years ended December 31:

	2017					2016
	Options Outstanding			Weighted Average Exercise Price		Options Outstanding			Weighted Average Exercise Price
Beginning Balance		4,354		$	2,295.37		3,260		$	3,664.61
Granted		34,651		$	11.57		2,257		$	543.63
Exercised		—			—		—			—
Forfeited/expired		(2,643	)	$	2,666.48		(1,163	)	$	2,729.60
Outstanding at December 31		36,362		$	91.48		4,354		$	2,295.37
Vested at December 31		2,344		$	964.27		2,134		$	3,780.79

For options outstanding and vested at December 31, 2017, the weighted average remaining contractual life was 9.33 years and 8.29 years, respectively. There were no option exercises in 2017 or 2016. The total fair value of options that vested in 2017 and 2016 was $0.7 million, and $1.1 million, respectively, at the fair value of the options as of the date of grant.

Valuation Assumptions: The fair value of each stock option is estimated at the grant date using the Black-Scholes option pricing model. The fair value of stock options under the Black-Scholes option pricing model requires management to make assumptions regarding projected employee stock option exercise behaviors, risk-free interest rates, volatility of the Company’s stock price, and expected dividends.

The Company has not historically paid cash dividends to its stockholders, and currently does not anticipate paying any cash dividends in the foreseeable future. As a result, the Company has assumed a dividend yield of 0%. The risk-free interest rate is based upon the rates of U.S. Treasury bills with a term that approximates the expected life of the option. Since the Company has limited historical exercise data to reasonably estimate the expected life of its option awards, the expected life is calculated using a simplified method. Expected volatility is based on historical volatility of the Company’s stock.

The following table provides the weighed average assumptions used in the Black-Scholes option pricing model for the years ended December 31:

	2017			2016
Expected dividend yield		0	%		0	%
Risk-free interest rate		1.97	%		1.71	%
Expected volatility		103	%		86	%
Expected life (in years)		6.25			6.25

The weighted-average fair value of stock options granted in 2017 and 2016 was $11.97 and $543.63, respectively. As of December 31, 2017, the total compensation cost related to all non-vested stock option awards not yet recognized was approximately $744,000 and is expected to be recognized over the remaining weighted-average period of 3.1 years.

Restricted Stock Awards: The following table summarizes restricted stock award activity during 2017 and 2016:

	2017					2016
	RSUs			Weighted Average Grant Price		RSUs			Weighted Average Grant Price
Nonvested, beginning balance		499		$	583.29		15		$	2,574.00
Granted		138		$	108.20		1,131		$	553.88
Vested		(392	)	$	132.70		(619	)	$	443.40
Forfeited		—			—		(28	)	$	426.00
Nonvested at December 31		245		$	521.23		499		$	583.29

During 2017, and 2016, employees tendered restricted stock units totaling 15, and 165, respectively, to cover related payroll tax withholdings.

Warrants

Warrants to purchase 8,522,684, and 44,268 shares of common stock were outstanding at December 31, 2017 and 2016, respectively. As of December 31, 2017, warrants outstanding were exercisable at prices ranging from $4.50 to $383.57 per share, and are exercisable over a period ranging from eleven months to 7.5 years.

Fair Value of Financial Instruments (FY)

9 Months Ended

12 Months Ended

Sep. 30, 2018

Dec. 31, 2017

Fair Value of Financial Instruments

Note 6 - Fair Value of Financial Instruments

The Company’s financial instruments consist of cash and cash equivalents, warrants, and contingent consideration.

Pursuant to the requirements of ASC Topic 820 Fair Value Measurement, the Company’s financial assets and liabilities measured at fair value on a recurring basis are classified and disclosed in one of the following three categories:

·	Level 1 - Financial instruments with unadjusted quoted prices listed on active market exchanges.

Level 2 - Financial instruments lacking unadjusted, quoted prices from active market exchanges, including over the counter traded financial instruments. The prices for the financial instruments are determined using prices for recently traded financial instruments with similar underlying terms as well as directly or indirectly observable inputs, such as interest rates and yield curves that are observable at commonly quoted intervals.

·	Level 3 - Financial instruments that are not actively traded on a market exchange. This category includes situations where there is little, if any, market activity for the financial instrument. The prices are determined using significant unobservable inputs or valuation techniques.

The fair value of the Company’s common stock warrant liability related to the Original Warrants was calculated using a Monte Carlo valuation model and was classified as Level 3 in the fair value hierarchy. All Original Warrants were exercised during the nine months ended September 30, 2017. The fair value of the Company’s warrant liability related to the placement agent warrants was calculated using a Black Scholes valuation model and is classified as Level 3 in the fair value hierarchy. The following is a rollforward of the fair value of Level 3 warrants:

Nine months ended September 30, 2017 (in thousands)
Balance December 31, 2016	$	1,843
Change in fair value		(1,469	)
Exercise of warrants		(368	)
Ending balance as of September 30, 2017	$	6

Fair values were calculated using the following assumptions:

	As of Dec. 31, 2016			As of date of exercise
Risk-free interest rates, adjusted for continuous compounding		1.47/1.96	%		1.45-1.99	%
Term (years)		3.1/5.3			2.84-5.50
Expected volatility		55.3/49.8	%		49.9-58.5	%
Dates and probability of future equity raises	various			various

The fair value of the Company’s contingent consideration related to the acquisition of the Aquadex Business from Baxter in August 2016 (see Note 8 – Commitments and Contingencies), was $126,000 as of both September 30, 2018 and December 31, 2017. The fair value was initially measured based on the consideration expected to be transferred (probability-weighted), discounted back to present value, and it is considered a Level 3 instrument. The discount rate used was determined at the time of measurement in accordance with accepted valuation methods. The Company measures the liability on a recurring basis using Level 3 inputs including probabilities of payment and projected payment dates. Changes to any of the inputs may result in significantly higher or lower fair value measurements. There were no changes in the fair value of the contingent consideration subsequent to the initial measurement.

All cash equivalents are considered Level 1 measurements for all periods presented. The Company does not have any financial instruments classified as Level 2 or any other classified as Level 3 and there were no movements between these categories during the periods ended September 30, 2018 and December 31, 2017. The Company believes that the carrying amounts of all remaining financial instruments approximate their fair value due to their relatively short maturities.

Note 8 - Fair Value of Financial Instruments

The Company’s financial instruments consist of cash and cash equivalents, warrants, and contingent consideration.

Pursuant to the requirements of ASC Topic 820 “Fair Value Measurement,” the Company’s financial assets and liabilities measured at fair value on a recurring basis are classified and disclosed in one of the following three categories:

•

Level 1 - Financial instruments with unadjusted quoted prices listed on active market exchanges.

•

Level 2 - Financial instruments lacking unadjusted, quoted prices from active market exchanges, including over the counter traded financial instruments. The prices for the financial instruments are determined using prices for recently traded financial instruments with similar underlying terms as well as directly or indirectly observable inputs, such as interest rates and yield curves that are observable at commonly quoted intervals.

•

Level 3 - Financial instruments that are not actively traded on a market exchange. This category includes situations where there is little, if any, market activity for the financial instrument. The prices are determined using significant unobservable inputs or valuation techniques.

The fair value of the Company’s common stock warrant liability related to the investor warrants was calculated using a Monte Carlo valuation model and was classified as Level 3 in the fair value hierarchy. The fair value of the Company’s common stock warrant liability related to the placement agent warrants is calculated using a Black Scholes option pricing model and is classified as Level 3 in the fair value hierarchy.

The following is a rollforward of the fair value of Level 3 warrants:

(in thousands)
July 26, 2016 warrant issuance	$	1,883
November 3, 2016 warrant issuance		778
Change in fair value		(818	)
Ending balance December 31, 2016		1,843
Change in fair value		(1,475	)
Exercise of warrants		(368	)
Ending balance as of December 31, 2017	$	—

Fair values were calculated using the following assumptions:

	July 26, 2016			Nov. 3, 2016			Dec. 31, 2016
Risk-free interest rates, adjusted for continuous compounding		0.94	%		1.33	%		1.47/1.96	%
Term (years)		3.5			5.5			3.1/5.3
Expected volatility		78	%		41.4	%		55.3/49.8	%
Dates and probability of future equity raises		various			various			various

A significant change in the inputs used for the Monte Carlo and Black Scholes option pricing models such as the expected volatility, bond yield of equivalent securities, or probability of future equity financings, in isolation, would result in significantly higher or lower fair value measurements. In combination, changes in these inputs could result in a significantly higher or lower fair value measurement if the input changes were to be aligned or could result in a minimally higher or lower fair value measurement if the input changes were of a compensating nature.

The fair value of the Company’s contingent consideration, as described in Note 2, was initially measured based on the consideration expected to be transferred (probability-weighted), discounted back to present value, and it is considered a Level 3 instrument. The discount rate used was determined at the time of measurement in accordance with accepted valuation methods. The Company measures the liability on a recurring basis using Level 3 inputs including probabilities of payment and projected payment dates. Changes to any of the inputs may result in significantly higher or lower fair value measurements. There were no changes in the fair value of the contingent consideration subsequent to the initial measurement.

All cash equivalents are considered Level 1 measurements for all periods presented. The Company does not have any financial instruments classified as Level 2 or any other classified as Level 3 and there were no movements between these categories during the periods ended December 31, 2017 and 2016. The Company believes that the carrying amounts of all remaining financial instruments approximate their fair value due to their relatively short maturities.

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

Nature of Business and Significant Accounting Policies [Abstract]

Income Taxes (FY)

9 Months Ended

12 Months Ended

Sep. 30, 2018

Dec. 31, 2017

Income Taxes [Abstract]

Income Taxes

Note 7 – Income Taxes

The Company provides for a valuation allowance when it is more likely than not that it will not realize a portion of the deferred tax assets. The Company has established a full valuation allowance for U.S. and foreign deferred tax assets due to the uncertainty that enough taxable income will be generated in those taxing jurisdictions to utilize the assets. Therefore, the Company has not reflected any benefit of such deferred tax assets in the accompanying consolidated financial statements.

As of September 30, 2018, there were no material changes to what the Company disclosed regarding tax uncertainties or penalties in its Annual Report on Form 10-K for the year ended December 31, 2017.

Note 9—Income Taxes

Domestic and foreign loss before income taxes, consists of the following for the years ended December 31:

(in thousands)	2017			2016
Domestic	$	(13,367	)	$	(15,877	)
Foreign		(9	)		31
Loss before income taxes	$	(13,376	)	$	(15,846	)

The components of income tax benefit (expense) consist of the following for the years ended December 31:

(in thousands)	2017			2016
Current:
United States and state	$	—		$	—
Foreign, net		(6	)		54
Deferred:
United States and state		—			—
Foreign		—			—
Total income tax benefit (expense)	$	(6	)	$	54

Actual income tax benefit (expense) differs from statutory federal income tax benefit (expense) as follows for the years ended December 31:

(in thousands)	2017			2016
Statutory federal income tax benefit	$	4,548		$	5,388
State tax benefit, net of federal taxes		48			2
Foreign tax		—			3
R&D tax credit		—			80
Foreign deferred exchange rate adjustments		899			—
Nondeductible/nontaxable items		(114	)		(86	)
New federal rate adjustment		(16,081	)		—
Other		(1,085	)		(257	)
Valuation allowance decrease (increase)		11,779			(5,076	)
Total income tax benefit (expense)	$	(6	)	$	54

Deferred taxes consist of the following as of December 31:

(in thousands)	2017			2016
Deferred tax assets:
Noncurrent:
Accrued leave	$	32		$	43
Other accrued expenses		28			97
Stock based compensation		336			1,477
Net operating loss carryforward		38,947			49,720
Deferred rent		7			17
Other		108			777
Intangibles		895
R&D credit carryforward		531			531
Total deferred tax assets	$	40,884		$	52,662
Less: valuation allowance		(40,884	)		(52,662	)
Total	$	—		$	—

On December 22, 2017, the Tax Cuts and Jobs Act of 2017 (Tax Reform Act) was signed into law making significant changes to the Internal Revenue Code. Changes include a reduction in the corporate tax rates, changes to operating loss carry-forwards and carrybacks, and a repeal of the corporate alternative minimum tax. The legislation reduces the U.S. corporate income tax rates from 34% to 21%. As a result of the enacted law, the Company is required to revalue its deferred tax assets and liabilities at the new enacted rate. The Company re-measured the U.S. deferred income tax assets and liabilities balances using the new enacted tax rate. There was no income tax impact from the re-measurement due to the 100% valuation allowance on the Company’s deferred tax assets.

As of December 31, 2017, the Company had net operating loss (“NOLs”) carryforwards of approximately $120.2 million for U.S. federal income tax purposes, which expire between 2024 and 2037, and NOLs in the

Commonwealth of Australia of approximately AU$49.0 million which the Company can carry forward indefinitely. U.S. NOLs cannot be used to offset taxable income in foreign jurisdictions. In addition, future utilization of NOL carryforwards in the U.S. may be subject to certain limitations under Section 382 of the Internal Revenue Code.

The Company received $80,000 fully refundable research and development tax credits in 2016, related to qualified research and development expenditures of its Australian subsidiary for its tax years ended June 30, 2015, and recorded the benefit in the year that the refund was received. The Company received no refunds in 2017 as it has ceased its research and development activities in Australia.

The Company provides for a valuation allowance when it is more likely than not that it will not realize a portion of the deferred tax assets. The Company has established a valuation allowance for U.S. and foreign deferred tax assets due to the uncertainty that enough taxable income will be generated in those taxing jurisdictions to utilize the assets. Therefore, the Company has not reflected any benefit of such deferred tax assets in the accompanying financial statements. For the year ended December 31, 2017, the valuation allowance decreased by $11.8 million primarily as result of the impact of the tax reform re-measurement of deferred tax assets. For the year ended December 31, 2016 the valuation allowance increased by $5.8 million primarily due to current year operating losses. During 2017, the Company experienced an ownership change as defined in Section 382 of the Internal Revenue Code which will limit the ability to utilize the Company’s net operating losses (NOLs). The Company may have experienced additional ownership changes in earlier years further limiting the NOL carry-forwards that may be utilized. The Company has not yet completed a formal Section 382 analysis. The general limitation rules allow the Company to utilize its NOLs subject to an annual limitation that is determined by multiplying the federal long-term tax-exempt rate by the Company’s value immediately before the ownership change.

The accounting guidance related to uncertain tax positions prescribes a recognition threshold and measurement attribute for recognition and measurement of a tax position taken or expected to be taken in a tax return. It also provides guidance on de-recognition, classification, interest and penalties, accounting in interim periods, disclosure and transition. The Company had no material uncertain tax positions as of December 31, 2017 or 2016.

The Company recognizes interest and penalties on unrecognized tax benefits as well as interest received from favorable tax settlements within income tax expense. At December 31, 2017 and 2016, the Company recorded no accrued interest or penalties related to uncertain tax positions.

The tax years ended December 31, 2014 through December 31, 2017 remain open to examination by the Internal Revenue Service and for the various states where we are subject to taxation. Additionally, the returns of the Company’s Australian and Irish subsidiary are subject to examination by tax authorities of those jurisdictions for the tax years ended and subsequent to June 30, 2013 and December 31, 2014, respectively.

Commitments and Contingencies (FY)	9 Months Ended	12 Months Ended
Commitments and Contingencies (FY)	Sep. 30, 2018	Dec. 31, 2017
Commitments and Contingencies [Abstract]
Commitments and Contingencies	Note 8 - Commitments and Contingencies Leases: The Company leases office space under a non-cancelable operating lease with Capital Partners Industrial Fund I, LLLP that expires in March 2022. In August 2018, the Company entered into a Third Amendment to the lease, extending the term of the lease from March 31, 2019 to March 31, 2022. Beginning on April 1, 2019, the annual base rent shall be $9.00 per square foot, subject to annual increases of $0.25 per square foot. Rent expense is recognized using the straight-line method over the term of the lease. Employee Retirement Plan: The Company has a 401(k)-profit sharing plan that provides retirement benefit to substantially all full-time U.S. employees. Eligible employees may contribute a percentage of their annual compensation, subject to Internal Revenue Service limitations, with the Company matching a portion of the employee’s contributions at the discretion of the Company. Contingent Consideration: As part of the acquisition of the Aquadex Business from Baxter in August 2016, the Company agreed that if it disposes of any of the Aquadex assets for a price that exceeds $4.0 million within three years of the closing, it will pay Baxter 40% of the amount of such excess. In addition, it also agreed that if shares of its common stock cease to be publicly traded on the Nasdaq Capital Market, Baxter has the option to require the Company to repurchase, in cash, all or any part of the common shares held by Baxter at a price equal to their fair market value, as determined by a third-party appraiser.	Note 10—Commitments and Contingencies Leases The Company leases office space under a non-cancelable operating lease that expires in March 2019. The lease contains provisions for future annual inflationary adjustments. Rent expense is recognized using the straight-line method over the term of the lease. The Company leases office equipment under non-cancelable operating leases that expire at various times through February 2019. Rent expense related to operating leases was approximately $290,000, and $286,000 for the years ended December 31, 2017 and 2016, respectively. Future minimum lease payments under non-cancelable operating leases as of December 31, 2017, were approximately $212,000, $60,000, $7,000, $0, and $0 for each of the years ended December 31, 2018, through 2022, respectively. Employee Retirement Plan The Company has a 401(k) profit sharing plan that provides retirement benefit to substantially all full-time U.S. employees. Eligible employees may contribute a percentage of their annual compensation, subject to Internal Revenue Service limitations, with the Company matching a portion of the employee’s contributions at the discretion of the Company. Matching contributions totaled $138,000 and $122,000 for the years ended December 31, 2017 and 2016, respectively. Inventory Purchase Commitments In connection with the acquisition of the Aquadex Business, the Company entered into a manufacturing and supply agreement with Baxter that was to expire within a period not to exceed 18 months from the close of the transaction. In May 2017, the Company notified Baxter to cease the manufacturing of the Aquadex product line as of June 30, 2017. In connection with this notification, the Company agreed to purchase the remaining Aquadex inventory, which consists mainly of raw materials priced at cost, through February 2018, for a total of $2.4 million. As of December 31, 2017, the Company had purchased and paid $1.2 million of this inventory and $1.2 million remained to be purchased. Contingent Consideration As described on Note 2, the Company agreed that if it disposes of any of the Aquadex assets for a price that exceeds $4.0 million within three years of the closing, it will pay Baxter 40% of the amount of such excess. In addition, it also agreed that if shares of its common stock cease to be publicly traded on Nasdaq, Baxter has the option to require the Company to repurchase, in cash, all or any part of the common shares held by Baxter at a price equal to their fair market value, as determined by a third-party appraiser.

Segment and Geographic Information (FY)	12 Months Ended
Segment and Geographic Information (FY)	Dec. 31, 2017
Segment and Geographic Information [Abstract]
Segment and Geographic Information	Note 11—Segment and Geographic Information The Company has one reportable segment, cardiac and coronary disease products. At December 31, 2017, long-lived assets were located primarily in the United States.

Nature of Business and Basis of Presentation (Q3)

9 Months Ended

12 Months Ended

Sep. 30, 2018

Dec. 31, 2017

Nature of Business and Basis of Presentation

Note 1 – Nature of Business and Basis of Presentation

On May 23, 2017, the Company announced it was changing its name from Sunshine Heart, Inc. to CHF Solutions, Inc. to more appropriately reflect the direction of its business.

For further information, refer to the consolidated financial statements and notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2017.

(in thousands)	September 30, 2018		December 31, 2017
Finished Goods	$	810	$	902
Work in Process		91		217
Raw Materials		1,047		469
Total	$	1,948	$	1,588

	September 30
	2018		2017
Stock options		1,987,502		36,874
Restricted stock units		90		324
Warrants to purchase common stock		8,522,672		496,629
Series F convertible preferred stock		266,680		-
Total		10,776,944		533,827

The following table reconciles reported net loss with reported net loss per share for the periods ended September 30, 2017:

(in thousands, except per share amounts)	Three months			Nine Months
Net loss	$	(2,847	)	$	(6,245	)
Deemed dividend to preferred shareholders (see Note 4)		-			(2,851	)
Net loss after deemed dividend		(2,847	)		(9,096	)
Weighted average shares outstanding		626			359
Basic and diluted loss per share	$	(4.55	)	$	(25.36	)

Note 1—Nature of Business and Significant Accounting Policies

Nature of Business

Going Concern

The Company became a revenue generating company after acquiring the Aquadex Business in August 2016. The Company expects to incur additional losses in the near-term as it grows the Aquadex Business, including investments in expanding its sales and marketing capabilities, purchasing inventory, manufacturing components, and complying with the requirements related to being a U.S. public company. To become and remain profitable, the Company must succeed in expanding the adoption and market acceptance of the Aquadex FlexFlow. This will require the Company to succeed in training personnel at hospitals and effectively and efficiently manufacturing, marketing and distributing the Aquadex FlexFlow and related components. There can be no assurance that the Company will succeed in these activities, and it may never generate revenues sufficient to achieve profitability.

Basis of Presentation

Use of Estimates

Cash and Cash Equivalents

Accounts Receivable

Inventories

Inventories are recorded as the lower of cost or market using the first-in, first out method. Inventories consisted of the following as of December 31 (in thousands):

	2017		2016
Finished Goods	$	902	$	644
Work in Process		217		—
Raw Materials		469		33
Total	$	1,588	$	677

Other Current Assets

Other current assets represent prepayments and deposits made by the Company.

Property, Plant and Equipment

Office furniture and equipment	5-15 years
Computer software and equipment	3-4 years
Laboratory and research equipment	3-15 years
Production equipment	3-7 years
Leasehold improvements and capital lease asset	3-5 years

Depreciation expense was $229,000 and $419,000 for the years ended December 31, 2017, and 2016, respectively.

Intangible assets

Amortization expense was $540,000 and $278,000 for the years ended December 31, 2017 and 2016, respectively.

Goodwill

Contingent consideration

Common stock warrant liability

Revenue Recognition

Foreign Currency Translation

Stock-Based Compensation

See Note 7- Stock Based Compensation, for further information regarding the assumptions used to calculate the fair value of share-based compensation.

Income Taxes

Loss per share

	December 31,
	2017		2016
Stock options		36,362		4,354
Restricted stock units		245		499
Warrants to purchase common stock		8,522,684		44,268
Series B, C and D convertible preferred stock		—		53,179
Series F convertible preferred stock		842,940		—-
Total		9,402,231		102,300

The following table reconciles reported net loss with reported net loss per share for the years ended December 31:

(in thousands, except per share amounts)	2017			2016
Net loss	$	(13,382	)	$	(15,792	)
Deemed dividend to preferred shareholders (see Note 6)		(11,590	)		(1,900	)
Net loss after deemed dividend		(24,972	)		(17,692	)
Weighted average shares outstanding		665			33
Basic and diluted loss per share	$	(37.51	)	$	(536.12	)

Research and Development

Reclassification

Recent Accounting Pronouncements

The Company evaluates events through the date the consolidated financial statements are filed for events requiring adjustment to or disclosure in the consolidated financial statements.

Revenue Recognition (Q3)	9 Months Ended
Revenue Recognition (Q3)	Sep. 30, 2018
Revenue Recognition [Abstract]
Revenue Recognition	Note 2 – Revenue Recognition Net Sales The Company sells its products in the United States primarily through a direct sales force. Customers who purchase the Company’s products include hospitals and clinics throughout the United States. In countries outside the United States, the Company sells its products through a limited number of specialty healthcare distributors in the United Kingdom, Italy, Spain, Germany, and Southeast Asia. The majority of these distributors resell the Company’s products to hospitals and clinics in their respective geographies. Revenue from product sales are recognized when the customer or distributor obtains control of the product, which occurs at a point in time, most frequently upon shipment of the product or receipt of the product, depending on shipment terms. The Company’s standard shipping terms are FOB shipping point, unless the customer requests that control and title to the inventory transfer upon delivery. Revenue includes shipment and handling fees charged to customers. Revenue is measured as the amount of consideration the Company expects to receive, adjusted for any applicable estimates of variable consideration and other factors affecting the transaction price, which is based on the invoiced price, in exchange for transferring products. All revenue is recognized when the Company satisfies its performance obligations under the contract. The majority of the Company’s contracts have a single performance obligation and are short term in nature. The Company has entered into extended service plans with customers that are recognized over time. Revenue from extended service plans represents less than 1% of net sales for the both the three- and nine-month periods ended September 30, 2018. The unfulfilled performance obligations related to these extended service plans is included in deferred revenue in the amount of $41,250 and $38,000 as of September 30, 2018 and December 31, 2017, respectively. Deferred revenue is included in other current liabilities on the condensed consolidated balance sheets. The majority of the deferred revenue is expected to be recognized within one year. Sales taxes and value added taxes in foreign jurisdictions that are collected from customers and remitted to governmental authorities are accounted for on a net basis and therefore are excluded from net sales. Revenue includes shipment and handling fees charged to customers. Shipping and handling costs associated with outbound freight after control over a product has transferred to a customer are accounted for as a fulfillment cost and are included in cost of goods sold. Product Returns: The Company offers customers a limited right of return for its product in case of non-conformity or performance issues. The Company estimates the amount of its product sales that may be returned by its customers and records this estimate as a reduction of revenue in the period the related product revenue is recognized. The Company currently estimates product return liabilities using available industry data and its own historical sales and returns information. The Company has not received any returns to date and believes that future returns of its products will be minimal. Therefore, revenue recognized is not currently impacted by variable consideration related to product returns.

Debt (Q3)	9 Months Ended	12 Months Ended
Debt (Q3)	Sep. 30, 2018	Dec. 31, 2017
Debt [Abstract]
Debt	Note 3 – Debt On August 5, 2016, the Company entered into a loan and security agreement with Silicon Valley Bank (the “Bank”) for a $1.0 million revolving line of credit (the “Revolving Line”). Under the Revolving Line, the Company may borrow the lesser of $1.0 million or 80% of its eligible accounts (subject to customary exclusions), minus the outstanding principal balance of any advances under the Revolving Line. Advances under the Revolving Line, if any, accrue interest at a floating annual rate equal to 1.75% or 1.0% above the prime rate, depending on liquidity factors. The loan agreement contains customary representations, as well as customary affirmative and negative covenants. Outstanding borrowings, if any, are collateralized by all of the Company’s assets, excluding intellectual property which is subject to a negative pledge. Advances under the Revolving Line are subject to various conditions precedent, including compliance with financial covenants relating to net liquidity relative to monthly cash burn, which the Company may or may not meet depending on its cash position at any given point. The Revolving Line expires March 31, 2020. There were no borrowings outstanding under this facility as of September 30, 2018 or December 31, 2017. Warrants: In connection with the funding of term loans under prior agreements, the Company issued warrants to purchase 115 shares of common stock at an exercise price of $3,132 per share and warrants to purchase 55 shares of common stock at an exercise price of $2,208 per share to the Bank and one of its affiliates. The Company valued these warrants at $2,316 per share and $1,626 per share, respectively, utilizing the Black Scholes valuation model and the following assumptions: an expected dividend yield of 0%, an expected stock price volatility of 88.07% and 87.04%, a risk-free interest rate of 1.86% and 2.20%, and an expected life of 6.25 years. The warrants were fully vested on the date of grant and expire on February 2025, and June 2025, respectively.	Note 5—Debt Prior Loan Agreement: On February 18, 2015, the Company entered into a loan and security agreement with Silicon Valley Bank (the Bank) for proceeds of up to $10.0 million at an annual interest rate of 7.0%. Under this agreement, a $6.0 million term loan was funded at closing and an additional term loan in the amount of $2.0 million was funded on June 26, 2015. The proceeds from the term loans were used for general corporate and working capital purposes. Commencing on January 1, 2016, the Company began repaying the advances made in twenty-four consecutive equal monthly installments. On August 4, 2016, the Company repaid all amounts outstanding under its existing debt facility of $5.5 million and incurred a $0.5 million loss on early extinguishment of debt, including the accelerated write-off of unamortized warrants and debt issuance costs. There were no borrowings outstanding under this facility as of December 31, 2017 or 2016. Warrants: In connection with the funding of these term loans, the Company issued 115 warrants at an exercise price of $3,132 per share and 55 warrants at an exercise price of $2,208 per share to the Bank and one of its affiliates. The Company valued these warrants at $2,316 per share and $1,626 per share, respectively, utilizing the Black Scholes option pricing model and the following assumptions: an expected dividend yield of 0%, an expected stock price volatility of 88.07% and 87.04%, a risk-free interest rate of 1.86% and 2.20%, and an expected life of 6.25 years. The warrants have a life of ten years and were fully vested at the date of grant. New Loan Agreement: On August 5, 2016, the Company entered into a new loan and security agreement with the Bank (the “New Loan Agreement”). Under the New Loan Agreement, the Bank agreed to provide the Company with up to $5.0 million in debt financing, consisting of a term loan in an aggregate original principal amount not to exceed $4.0 million (the “Term Loan”) and a revolving line of credit in an aggregate principal amount not to exceed $1.0 million outstanding at any time (the “Revolving Line”; together with the Term Loan, the “Loans”). Proceeds from the Loans were to be used for general corporate and working capital purposes. Advances under the Term Loan were available to the Company until November 30, 2016 and were subject to the Company’s compliance with liquidity covenants. The Term Loan expired unused on November 30, 2016. Advances under the Revolving Line are available to the Company until March 31, 2020 and accrue interest at a floating annual rate equal to 1.75% or 1.0% above the prime rate, depending on liquidity factors. Outstanding borrowings, if any, are collateralized by all of the Company’s assets, excluding intellectual property which is subject to a negative pledge. There were no borrowings outstanding under this facility as of December 31, 2017 or 2016.

Equity (Q3)	9 Months Ended	12 Months Ended
Equity (Q3)	Sep. 30, 2018	Dec. 31, 2017
Equity [Abstract]
Equity	Note 4 – Equity Series B/B-1 Convertible Preferred Stock: On July 20, 2016, the Company entered into a securities purchase agreement with an institutional investor for an offering of shares of convertible preferred stock and warrants with gross proceeds of approximately $3.5 million in a registered direct offering. The Series B issued under the securities purchase agreement was exchanged for Series B-1 Convertible Preferred Stock on October 30, 2016. The Series B-1 Convertible Preferred Stock was non-voting and was convertible into shares of common stock at the holder’s election at any time. Approximately $1.6 million of the proceeds were allocated to the preferred stock, representing the residual proceeds after the warrants were recorded at fair value (see below.) As of September 30, 2018, and December 31, 2017, all Series B/B-1-Convertible Preferred Stock had been converted into common stock and none were outstanding. Series C and D Convertible Preferred Stock: On October 30, 2016, the Company entered into a securities purchase agreement with an institutional investor for shares of convertible preferred stock and warrants with an aggregate purchase price of $3.8 million in a registered direct offering and simultaneous private placement. The first closing of the transaction occurred on November 3, 2016, whereby the Company received $3.6 million in gross proceeds and the second closing occurred on January 10, 2017, whereby the Company received gross proceeds of $0.2 million. The Series C and D Convertible Preferred Stock issued in the transaction included a contingent beneficial conversion amount of $1.3 million and $0.5 million, respectively, representing the intrinsic value of the shares at the time of issuance. This amount is reflected as an increase to the loss per share allocable to common stockholders in the nine-month period ended September 30, 2017 when the contingency for the conversion was resolved with the shareholder approval allowing for the conversion of the preferred stock into common stock. As of September 30, 2018, and December 31, 2017, all shares of the Series C and D Convertible Preferred Stock had been converted into common stock and none were outstanding. Series E Convertible Preferred Stock: On April 24, 2017, the Company closed on an underwritten public offering of a total of 2.8 million shares of common stock, 6,400 shares of Series E Convertible Preferred Stock convertible into 6.4 million shares of common stock, and warrants to purchase 9.2 million shares of common stock for gross proceeds of $9.2 million, which included the full exercise of the underwriter’s over-allotment option to purchase additional shares and warrants. Net proceeds totaled approximately $8.0 million after deducting the underwriting discounts and commissions and other costs associated with the offering. The Series E Convertible Preferred Stock included a beneficial conversion amount of $1.0 million, representing the intrinsic value of the shares at the time of issuance. This amount is reflected as an increase to the loss per share allocable to common stockholders in the nine months ended September 30, 2017. As of September 30, 2018, and December 31, 2017, all shares of the Series E Convertible Preferred Stock had been converted into common stock and none were outstanding. Series F Convertible Preferred Stock: On November 27, 2017, the Company closed on an underwritten public offering of Series F Convertible Preferred Stock (“Series F preferred stock”) and warrants to purchase shares of common stock for gross proceeds of $18.0 million. Net proceeds totaled approximately $16.2 million after deducting the underwriting discounts and commissions and other costs associated with the offering. The offering was comprised of Series F preferred stock, convertible into shares of the Company’s common stock at a conversion price of $4.50 per share. Each share of Series F preferred stock was accompanied by a Series 1 warrant, which expires on the first anniversary of its issuance, to purchase 223 shares of the Company’s common stock at an exercise price of $4.50 per share, and a Series 2 warrant, which expires on the seventh anniversary of its issuance, to purchase 223 shares of the Company’s common stock at an exercise price of $4.50 per share. The Series F preferred stock and the warrants were immediately separable and were issued separately. The conversion price of the Series F preferred stock will be adjusted in the event of a stock split, combination, reclassification or stock dividend or if the Company consummates a fundamental transaction. The Series F preferred stock also has full ratchet price based anti-dilution protection, subject to customary carve outs, in the event of a down-round financing at a price per share below the conversion price of the Series F preferred stock (which protection will expire if, during any 20 of 30 consecutive trading days, the volume weighted average price of the Company’s common stock exceeds 300% of the then-effective conversion price of the Series F preferred stock and the daily dollar trading volume for each trading day during such period exceeds $200,000). The exercise price of the warrants is fixed and does not contain any variable pricing features, nor any price based anti-dilutive features, apart from customary adjustments for stock splits, combinations, reclassifications, stock dividends or fundamental transactions. A total of 18,000 shares of Series F Convertible Preferred Stock convertible into approximately 4.0 million shares of common stock and warrants to purchase approximately 8.0 million shares of common stock were issued in the offering. The Series F Convertible Preferred Stock included a beneficial conversion amount of $8.7 million, representing the intrinsic value of the shares at the time of issuance. As noted below, effective July 3, 2018, the conversion price of the Series F preferred stock was reduced from $4.50 to $2.12, the per share price to public in the July 2018 Offering described below, and now each share of the remaining Series F preferred stock is convertible into 472 shares of the Company’s common stock. As of September 30, 2018, and December 31, 2017, 17,435 and 14,220 shares of the Series F Convertible Preferred Stock had been converted into an aggregate of 3,899,210 and 3,171,060 shares of common stock and 565 and 3,780 remained outstanding, respectively. July 2018 Offering: On July 3, 2018, the Company closed on an underwritten public offering of 2,547,169 shares of its common stock at a public offering price of $2.12 per share, for gross proceeds of $5.4 million, including the full exercise of the underwriters’ over-allotment option to purchase additional shares of the Company’s common stock, prior to deducting underwriting discounts and commissions and offering expenses (the “July 2018 Offering”). In connection with the July 2018 Offering, and to induce certain institutional investors who hold warrants issued by the Company in November 2017 (“November 2017 Warrants”) to participate in the July 2018 Offering, the Company entered into letter agreements with such institutional investors (collectively, the “Warrant Reprice Agreements”). Pursuant to the terms of the Warrant Reprice Agreements, the Company agreed, effective July 3, 2018, to (a) reduce the per share exercise price of the November 2017 Warrants held by such institutional investors (the “Repriced Warrants”) to $2.12 and (b) extend the expiration date of the Repriced Warrants that were to expire on November 27, 2018 to November 27, 2019. The number of shares underlying the Repriced Warrants after the price reduction did not change. The Repriced Warrants are exercisable for 7,760,400 shares of common stock in the aggregate, of which, following such amendment, half expire on November 27, 2019 and half expire on November 27, 2024. The repricing of the warrants was accounted as an equity financing cost, with no impact to net proceeds from the offering. As noted above, the Company’s outstanding Series F preferred stock is subject to full-ratchet anti-dilution protection in the event the Company sells any common stock at a price lower than the then-conversion price of the Series F preferred stock. As a result of the July 2018 Offering, effective July 3, 2018, the conversion price of the Series F preferred stock was reduced from $4.50 to $2.12, the per share price to public in the July 2018 Offering. Placement Agent Fees: In connection with the issuance of the Series B, C and D Convertible Preferred Shares, the Company paid the placement agent an aggregate cash placement fee equal to 6% of the aggregate gross proceeds raised in the offering and issued warrants as described below. In connection with the issuance of the Series E and F Convertible Preferred Shares and the July 2018 Offering, the Company provided underwriting discounts and commissions of 9%, 8% and 8%, respectively, of the aggregate gross proceeds raised in the offering to the underwriters and issued no warrants to the underwriters in such transactions. Investor Warrants: In connection with the issuance of the Series B Convertible Preferred Stock in July 2016, the Company issued the investor, at no additional cost, warrants to purchase 6,149 shares of common stock at an exercise price of $564 per share. The warrants were exercisable for 36 months commencing six months from the closing date and were subject to a reduction of the exercise price if the Company subsequently issued common stock or equivalents at an effective price less than the current exercise price of such warrants. Concurrently with the closing of the Series C and D Convertible Preferred Stock and warrant financing on November 3, 2016, the exercise price for these warrants was adjusted to $102 per share. In connection with the issuance of the Series C and D Convertible Preferred Stock in November 2016, the Company issued the investor, at no additional cost, warrants to purchase 35,295 shares of common stock at an exercise price of $108 per share. In connection with the issuance of the Series D Convertible Preferred Stock at the second closing in January 2017, the Company issued the investor, at no additional cost, warrants to purchase 1,961 shares of common stock at an exercise price of $108 per share. The warrants were exercisable for 60 months commencing on the earlier of the day of the receipt of approval of the Company’s stockholders of a proposal to approve the issuance of the shares of common stock underlying the warrants, or the six-month anniversary of the date of issuance. These warrants were subject to a reduction of the exercise price if the Company subsequently issued common stock or equivalents at an effective price less than the current exercise price of such warrants. Warrant Exercise Agreement: On February 15, 2017, the Company entered into a letter agreement with the institutional investors that held the majority of its outstanding warrants (the ‘‘Original Warrants’’), to incent the cash exercise of the investor warrants described above on or before March 31, 2017. In exchange for any such exercise, the Company agreed to provide the investors a replacement warrant (the ‘‘Replacement Warrants’’) to purchase the same number of shares of common stock as were issued upon exercise of the Original Warrants, with an exercise price equal to the consolidated closing bid price of its common stock on the date of issuance. The Replacement Warrants were issued in the same form as the Original Warrants except the exercise prices are not subject to reduction for subsequent equity issuances and the Replacement Warrants do not allow the investor to demand that the Company purchase the Replacement Warrants in the event of a fundamental transaction involving the Company. In connection with this agreement, between February and March 2017, the investors exercised all of the Original Warrants for gross cash proceeds to the Company of $2.0 million, and the Company issued 43,396 Replacement Warrants with exercise prices ranging from $34.6 per share to $99.8 per share. The Company entered into the letter agreement with the investors to incent the exercise of the Original Warrants in order to receive the cash proceeds from the exercise of the Original Warrants and because the exercise of the Original Warrants would allow the Company to remove the warrant liability from its consolidated balance sheet and avoid future fair value adjustments and associated volatility in its consolidated financial statements, as the Replacement Warrants are not accounted for as liabilities based on their terms. As of September 30, 2018, and December 31, 2017, there were no Original Warrants outstanding and all Replacement Warrants under the letter agreement had been issued. Placement Agent Warrant: In connection with the issuance of the Series B, C and D Convertible Preferred Stock, the Company issued warrants to the placement agent to purchase an aggregate of 2,605 shares of common stock at exercise prices ranging from $126.0 per share to $810.0 per share. These warrants were issued at no additional cost, were exercisable immediately, and expire five years from the closing of each offering. These warrants do not contain repricing provisions. Warrant Valuation: Both the Original Warrants and placement agent warrants were accounted for as liabilities and were recorded at fair value on the date of issuance. These warrants must be measured and recorded at fair value for each subsequent reporting period that the warrants remain outstanding, and any changes in fair value must be recognized in the consolidated statement of operations. In connection with the warrant exchange agreement described above, the Company remeasured each Original Warrant as of the date of exercise and recorded $1.4 million for the change in fair value of these warrants as an unrealized gain in the accompanying consolidated statement of operations for the nine-month period ended September 30, 2017. The Replacement Warrants were valued at $0.5 million using the Black Scholes valuation model with the following assumptions: an expected dividend yield of 0%, expected stock price volatility of 49.65%-50.38%, risk-free interest rates of 1.95%-1.97% and an expected life of 5 years. The warrants have a five-year life and were fully vested at the date of grant. The terms of these warrants do not require them to be accounted for as liabilities and are therefore recorded in equity. As in incentive to early exercise the Original Warrants, the fair value provided to investors through the Replacement Warrants exceeded the fair value of the Original Warrants that was relinquished by the warrant holders by approximately $0.1 million, which has been reflected as an expense in the statement of operations for the nine-month period ending September 30, 2017.	Note 6—Shareholder’s Equity Series B/B-1 Convertible Preferred Stock: On July 20, 2016, the Company entered into a securities purchase agreement with an institutional investor for an offering of shares of convertible preferred stock and warrants with gross proceeds of approximately $3.5 million in a registered direct offering. The transaction closed on July 26, 2016, and the Company issued 3,468 shares of Series B Convertible Preferred Stock. The Series B Convertible Preferred Stock is non-voting and was convertible into a total of 6,149 shares of common stock at the holder’s election at any time at a conversion price of $564.0 per share. Approximately $1.6 million of the proceeds were allocated to the preferred stock, representing the residual proceeds after the warrants (described below) were recorded at fair value. On October 30, 2016, the Company entered into an exchange agreement with the holders of its Series B Convertible Preferred Stock and agreed to issue such holders 2,227.2 shares of the Company’s Series B-1 Convertible Preferred Stock in exchange for the cancellation of all shares of Series B Convertible Preferred Stock held by such holders. The Series B-1 Convertible Preferred Stock had similar terms as the Series B Convertible Preferred Stock, except that the initial conversion price of the Series B-1 Convertible Preferred Stock was $102 per share. As of December 31, 2016, 402.8 shares of the Series B-1 Convertible Preferred Stock had been converted into 3,948 shares of common stock, and 1,824.4 shares of Series B-1 Convertible Preferred Stock remained outstanding. As of December 31, 2017, all remaining Series B-1 Convertible Preferred Stock had been converted into an additional 17,866 shares of common stock and none remained outstanding. The Series B and B-1 convertible preferred stock include a net deemed dividend in the amount of $1.9 million, representing the intrinsic value of the shares at the time of issuance, which is reflected as an increase to the loss per share allocable to common shareholders. Series C and D Convertible Preferred Stock: Also, on October 30, 2016, the Company entered into a securities purchase agreement with an institutional investor for shares of convertible preferred stock and warrants with an aggregate purchase price of $3.8 million in a registered direct offering and simultaneous private placement. The first closing of the transaction occurred on November 3, 2016, whereby the Company received $3.6 million in gross proceeds and issued and sold 2,900 shares of Series C Convertible Preferred Stock, and 700 shares of Series D Convertible Preferred Stock, both with conversion prices of $102 per share. At the second closing, on January 10, 2017, the Company issued and sold 200 shares of Series D Convertible Preferred Stock with a conversion price of $102 per share for gross proceeds of $0.2 million. The Series C and D Convertible Preferred Stock included a contingent beneficial conversion amount of $1.3 million and $0.5 million, respectively, representing the intrinsic value of the shares at the time of issuance. This amount is reflected as an increase to the loss per share allocable to common stockholders in the first quarter of 2017 when the contingency for the conversion was resolved with the shareholder approval allowing for the conversion of the preferred stock into common stock. As of December 31, 2016, 2,900 shares of Series C Convertible Preferred Stock and 700 shares of Series D Convertible Preferred Stock were outstanding, and none had been converted. As of December 31, 2017, all shares of the Series C and D Convertible Preferred Stock had been converted into an aggregate of 55,712 shares of common stock and none remained outstanding. The Series D Convertible Preferred Stock with a carrying value of $0.5 million was classified as temporary equity in the consolidated balance sheet as of December 31, 2016 because the Company could not control the settlement of its redemption in common stock. The temporary equity was not remeasured to fair value each period through earnings because the events that could trigger its redemption were not probable of occurrence. There were no shares of the Series D Convertible Preferred Stock outstanding as of December 31, 2017. Series E Convertible Preferred Stock: On April 24, 2017, the Company closed on an underwritten public offering of common stock, Series E Convertible Preferred Stock and warrants to purchase shares of common stock for gross proceeds of $9.2 million, which included the full exercise of the underwriter’s over-allotment option to purchase additional shares and warrants. Net proceeds totaled approximately $8.0 million after deducting the underwriting discounts and commissions and other costs associated with the offering. The offering comprised of Class A Units, priced at a public offering price of $20.00 per unit, with each unit consisting of one share of common stock and one five-year warrant to purchase one share of common stock with an exercise price of $22 per share, and Class B Units, priced at a public offering price of $1,000 per unit, with each unit comprised of one share of preferred stock, which was convertible into 50 shares of common stock, and warrants to purchase 50 shares of common stock, also with an exercise price of $22 per share. The conversion price of the Series E Convertible Preferred Stock as well as the exercise price of the warrants are fixed and do not contain any variable pricing features nor any price based anti-dilutive features apart from customary adjustments for splits and reverse splits of common stock. A total of 140,000 shares of common stock, 6,400 shares of Series E Convertible Preferred Stock convertible into 320,000 shares of common stock and warrants to purchase 640,000 shares of common stock were issued in the offering including the full exercise of the underwriter’s over-allotment option to purchase additional shares and warrants. The Series E Convertible Preferred Stock included a beneficial conversion amount of $1.0 million, representing the intrinsic value of the shares at the time of issuance. This amount is reflected as an increase to the loss per share allocable to common stockholders in the year ended December 31, 2017. As of December 31, 2017, all shares of the Series E Convertible Preferred Stock had been converted into an aggregate of 320,000 shares of common stock and none remained outstanding. Series F Convertible Preferred Stock: On November 27, 2017, the Company closed on an underwritten public offering Series F Convertible Preferred Stock and warrants to purchase shares of common stock for gross proceeds of $18.0 million. Net proceeds totaled approximately $16.2 million after deducting the underwriting discounts and commissions and other costs associated with the offering. The offering was comprised of Series F preferred stock, convertible into shares of the Company’s common stock at a conversion price of $4.50 per share. Each share of Series F preferred stock was accompanied by a Series 1 warrant, which expires on the first anniversary of its issuance, to purchase 223 shares of the Company’s common stock at an exercise price of $4.50 per share, and a Series 2 warrant, which expires on the seventh anniversary of its issuance, to purchase 223 shares of the Company’s common stock at an exercise price of $4.50 per share. The Series F preferred stock and the warrants were immediately separable and were issued separately. The conversion price of the Series F Convertible Preferred Stock as well as the exercise price of the warrants are fixed and do not contain any variable pricing features, nor any price based anti-dilutive features apart from customary adjustments for splits and reverse splits of common stock. A total of 18,000 shares of Series F Convertible Preferred Stock convertible into approximately 4.0 million shares of common stock and warrants to purchase approximately 8.0 million shares of common stock were issued in the offering. The Series F Convertible Preferred Stock included a beneficial conversion amount of $8.7 million, representing the intrinsic value of the shares at the time of issuance. This amount is reflected as an increase to the loss per share allocable to common stockholders in the year ended December 31, 2017. As of December 31, 2017, 14,220 shares of the Series F Convertible Preferred Stock had been converted into an aggregate of 3,171,060 shares of common stock and 3,780 remained outstanding. In connection with the issuance of the Series B, C and D Convertible Preferred Shares, the Company paid the placement agent an aggregate cash placement fee equal to 6% of the aggregate gross proceeds raised in the offering and issued warrants as described below. In connection with the issuance of the Series E and F Convertible Preferred Shares, the Company paid the placement agent an aggregate cash placement fee equal to 9% and 8%, respectively, of the aggregate gross proceeds raised in the offering and issued no warrants to the placement agent. Investor Warrants: In connection with the issuance of the Series B Convertible Preferred Stock in July 2016, the Company issued the investor at no additional cost warrants to purchase 6,149 shares of common stock at an exercise price of $564 per share. The warrants were exercisable for 36 months commencing six months from the closing date and were subject to a reduction of the exercise price if the Company subsequently issued common stock or equivalents at an effective price less than the current exercise price of such warrants. Concurrently with the closing of the Series C and D Convertible Preferred Stock and warrant financing on November 3, 2016, the exercise price for these warrants was adjusted to $102 per share. In connection with the issuance of the Series C and D Convertible Preferred Stock in November 2016, the Company issued the investor at no additional cost warrants to purchase 35,295 shares of common stock at an exercise price of $108 per share. In connection with the issuance of the Series D Convertible Preferred Stock at the second closing in January 2017, the Company issued the investor at no additional cost warrants to purchase 1,961 shares of common stock at an exercise price of $108 per share. The warrants were exercisable for 60 months commencing on the earlier of the day of the receipt of approval of the Company’s stockholders of a proposal to approve the issuance of the shares of common stock underlying the warrants, or the six-month anniversary of the date of issuance. These warrants were subject to a reduction of the exercise price if the Company subsequently issued common stock or equivalents at an effective price less than the current exercise price of such warrants. Warrant Exercise Agreement: On February 15, 2017, the Company entered into a letter agreement with the institutional investors that held the majority of its outstanding warrants (the “Original Warrants”), to incent the cash exercise of these warrants on or before March 31, 2017. In exchange for any such exercise, the Company agreed to provide the investors a replacement warrant (the “Replacement Warrants”) to purchase the same number of shares of common stock as were issued upon exercise of the Original Warrants, with an exercise price equal to the consolidated closing bid price of its common stock on the date of issuance. The Replacement Warrants were issued in the same form as the Original Warrants except the exercise prices are not subject to reduction for subsequent equity issuances and the Replacement Warrants do not allow the investor to demand that the Company purchase the Replacement Warrants in the event of a fundamental transaction involving the Company. In connection with this agreement, between February and March 2017, the investors exercised all of the Original Warrants for gross cash proceeds to the Company of $2.0 million, and the Company issued 43,396 Replacement Warrants with exercise prices ranging from $34.6 per share to $99.8 per share. The Company entered into the letter agreement with the investors to incent the exercise of the Original Warrants in order to receive the cash proceeds from the exercise of the Original Warrants and because the exercise of the Original Warrants would allow the Company to remove the warrant liability from its balance sheet and avoid future fair value adjustments and associated volatility in its consolidated financial statements, as the Replacement Warrants are not accounted for as liabilities based on their terms. As of December 31, 2017, there were no Original Warrants outstanding and all Replacement Warrants under the letter agreement had been issued. Warrant Valuation: Both the Original Warrants and placement agent warrants were accounted for as liabilities and were recorded at fair value on the date of issuance. These warrants must be measured and recorded at fair value for each subsequent reporting period that the warrants remain outstanding, and any changes in fair value must be recognized in the consolidated statement of operations. In connection with the warrant exchange agreement described above, the Company remeasured each Original Warrant as of the date of exercise and recorded $1.5 million for the change in fair value of these warrants as an unrealized gain in the accompanying consolidated statement of operations for year ended December 31, 2017. The warrant liability totaled $1.8 million as of December 31, 2016 and $0 as of December 31, 2017. The Replacement Warrants were valued at $0.5 million using the Black Scholes option pricing model with the following assumptions: an expected dividend yield of 0%, expected stock price volatility of 49.65%-50.38%, risk-free interest rates of 1.95%-1.97% and an expected life of 5 years. The warrants have a five-year life and were fully vested at the date of grant. The terms of the Replacement Warrants do not require them to be accounted for as liabilities and are therefore recorded in equity. As in incentive to early exercise the Original Warrants, the fair value provided to investors through the Replacement Warrants exceeded the fair value of the Original Warrants that was relinquished by the warrant holders by approximately $0.1 million, which has been reflected as an expense in the consolidated statement of operations for the year ended December 31, 2017.

Stock-Based Compensation (Q3)

9 Months Ended

12 Months Ended

Sep. 30, 2018

Dec. 31, 2017

Stock-Based Compensation

Note 5 - Stock-Based Compensation

The following table presents the classification of stock-based compensation expense recognized for the periods below:

	Three months ended September 30,					Nine months ended September 30,
(in thousands)	2018			2017		2018		2017
Selling, general and administrative expense	$	440		$	106	$	1,446	$	351
Research and development expense		(3	)		5		98		43
Total stock-based compensation expense	$	437		$	111	$	1,544	$	394

Note 7— Stock-Based Compensation

Stock Options and Restricted Stock Awards

(Dollars in thousands)	2017		2016
Selling, general and administrative	$	452	$	630
Research and development		50		385
Total	$	502	$	1,015

Stock Options: The following is a summary of the Plans’ stock option activity during the years ended December 31:

	2017					2016
	Options Outstanding			Weighted Average Exercise Price		Options Outstanding			Weighted Average Exercise Price
Beginning Balance		4,354		$	2,295.37		3,260		$	3,664.61
Granted		34,651		$	11.57		2,257		$	543.63
Exercised		—			—		—			—
Forfeited/expired		(2,643	)	$	2,666.48		(1,163	)	$	2,729.60
Outstanding at December 31		36,362		$	91.48		4,354		$	2,295.37
Vested at December 31		2,344		$	964.27		2,134		$	3,780.79

The following table provides the weighed average assumptions used in the Black-Scholes option pricing model for the years ended December 31:

	2017			2016
Expected dividend yield		0	%		0	%
Risk-free interest rate		1.97	%		1.71	%
Expected volatility		103	%		86	%
Expected life (in years)		6.25			6.25

Restricted Stock Awards: The following table summarizes restricted stock award activity during 2017 and 2016:

	2017					2016
	RSUs			Weighted Average Grant Price		RSUs			Weighted Average Grant Price
Nonvested, beginning balance		499		$	583.29		15		$	2,574.00
Granted		138		$	108.20		1,131		$	553.88
Vested		(392	)	$	132.70		(619	)	$	443.40
Forfeited		—			—		(28	)	$	426.00
Nonvested at December 31		245		$	521.23		499		$	583.29

During 2017, and 2016, employees tendered restricted stock units totaling 15, and 165, respectively, to cover related payroll tax withholdings.

Warrants

Fair Value of Financial Instruments (Q3)

9 Months Ended

12 Months Ended

Sep. 30, 2018

Dec. 31, 2017

Fair Value of Financial Instruments

Note 6 - Fair Value of Financial Instruments

The Company’s financial instruments consist of cash and cash equivalents, warrants, and contingent consideration.

·	Level 1 - Financial instruments with unadjusted quoted prices listed on active market exchanges.

·	Level 3 - Financial instruments that are not actively traded on a market exchange. This category includes situations where there is little, if any, market activity for the financial instrument. The prices are determined using significant unobservable inputs or valuation techniques.

Nine months ended September 30, 2017 (in thousands)
Balance December 31, 2016	$	1,843
Change in fair value		(1,469	)
Exercise of warrants		(368	)
Ending balance as of September 30, 2017	$	6

Fair values were calculated using the following assumptions:

	As of Dec. 31, 2016			As of date of exercise
Risk-free interest rates, adjusted for continuous compounding		1.47/1.96	%		1.45-1.99	%
Term (years)		3.1/5.3			2.84-5.50
Expected volatility		55.3/49.8	%		49.9-58.5	%
Dates and probability of future equity raises	various			various

Note 8 - Fair Value of Financial Instruments

The Company’s financial instruments consist of cash and cash equivalents, warrants, and contingent consideration.

•

Level 1 - Financial instruments with unadjusted quoted prices listed on active market exchanges.

•

The following is a rollforward of the fair value of Level 3 warrants:

(in thousands)
July 26, 2016 warrant issuance	$	1,883
November 3, 2016 warrant issuance		778
Change in fair value		(818	)
Ending balance December 31, 2016		1,843
Change in fair value		(1,475	)
Exercise of warrants		(368	)
Ending balance as of December 31, 2017	$	—

Fair values were calculated using the following assumptions:

	July 26, 2016			Nov. 3, 2016			Dec. 31, 2016
Risk-free interest rates, adjusted for continuous compounding		0.94	%		1.33	%		1.47/1.96	%
Term (years)		3.5			5.5			3.1/5.3
Expected volatility		78	%		41.4	%		55.3/49.8	%
Dates and probability of future equity raises		various			various			various

All cash equivalents are considered Level 1 measurements for all periods presented. The Company does not have any financial instruments classified as Level 2 or any other classified as Level 3 and there were no movements between these categories during the periods ended December 31, 2017 and 2016. The Company believes that the carrying amounts of all remaining financial instruments approximate their fair value due to their relatively short maturities.

Nature of Business and Significant Accounting Policies [Abstract]

Income Taxes (Q3)

9 Months Ended

12 Months Ended

Sep. 30, 2018

Dec. 31, 2017

Income Taxes [Abstract]

Income Taxes

Note 7 – Income Taxes

As of September 30, 2018, there were no material changes to what the Company disclosed regarding tax uncertainties or penalties in its Annual Report on Form 10-K for the year ended December 31, 2017.

Note 9—Income Taxes

Domestic and foreign loss before income taxes, consists of the following for the years ended December 31:

(in thousands)	2017			2016
Domestic	$	(13,367	)	$	(15,877	)
Foreign		(9	)		31
Loss before income taxes	$	(13,376	)	$	(15,846	)

The components of income tax benefit (expense) consist of the following for the years ended December 31:

(in thousands)	2017			2016
Current:
United States and state	$	—		$	—
Foreign, net		(6	)		54
Deferred:
United States and state		—			—
Foreign		—			—
Total income tax benefit (expense)	$	(6	)	$	54

Actual income tax benefit (expense) differs from statutory federal income tax benefit (expense) as follows for the years ended December 31:

(in thousands)	2017			2016
Statutory federal income tax benefit	$	4,548		$	5,388
State tax benefit, net of federal taxes		48			2
Foreign tax		—			3
R&D tax credit		—			80
Foreign deferred exchange rate adjustments		899			—
Nondeductible/nontaxable items		(114	)		(86	)
New federal rate adjustment		(16,081	)		—
Other		(1,085	)		(257	)
Valuation allowance decrease (increase)		11,779			(5,076	)
Total income tax benefit (expense)	$	(6	)	$	54

Deferred taxes consist of the following as of December 31:

(in thousands)	2017			2016
Deferred tax assets:
Noncurrent:
Accrued leave	$	32		$	43
Other accrued expenses		28			97
Stock based compensation		336			1,477
Net operating loss carryforward		38,947			49,720
Deferred rent		7			17
Other		108			777
Intangibles		895
R&D credit carryforward		531			531
Total deferred tax assets	$	40,884		$	52,662
Less: valuation allowance		(40,884	)		(52,662	)
Total	$	—		$	—

Commitments and Contingencies (Q3)	9 Months Ended	12 Months Ended
Commitments and Contingencies (Q3)	Sep. 30, 2018	Dec. 31, 2017
Commitments and Contingencies [Abstract]
Commitments and Contingencies	Note 8 - Commitments and Contingencies Leases: The Company leases office space under a non-cancelable operating lease with Capital Partners Industrial Fund I, LLLP that expires in March 2022. In August 2018, the Company entered into a Third Amendment to the lease, extending the term of the lease from March 31, 2019 to March 31, 2022. Beginning on April 1, 2019, the annual base rent shall be $9.00 per square foot, subject to annual increases of $0.25 per square foot. Rent expense is recognized using the straight-line method over the term of the lease. Employee Retirement Plan: The Company has a 401(k)-profit sharing plan that provides retirement benefit to substantially all full-time U.S. employees. Eligible employees may contribute a percentage of their annual compensation, subject to Internal Revenue Service limitations, with the Company matching a portion of the employee’s contributions at the discretion of the Company. Contingent Consideration: As part of the acquisition of the Aquadex Business from Baxter in August 2016, the Company agreed that if it disposes of any of the Aquadex assets for a price that exceeds $4.0 million within three years of the closing, it will pay Baxter 40% of the amount of such excess. In addition, it also agreed that if shares of its common stock cease to be publicly traded on the Nasdaq Capital Market, Baxter has the option to require the Company to repurchase, in cash, all or any part of the common shares held by Baxter at a price equal to their fair market value, as determined by a third-party appraiser.	Note 10—Commitments and Contingencies Leases The Company leases office space under a non-cancelable operating lease that expires in March 2019. The lease contains provisions for future annual inflationary adjustments. Rent expense is recognized using the straight-line method over the term of the lease. The Company leases office equipment under non-cancelable operating leases that expire at various times through February 2019. Rent expense related to operating leases was approximately $290,000, and $286,000 for the years ended December 31, 2017 and 2016, respectively. Future minimum lease payments under non-cancelable operating leases as of December 31, 2017, were approximately $212,000, $60,000, $7,000, $0, and $0 for each of the years ended December 31, 2018, through 2022, respectively. Employee Retirement Plan The Company has a 401(k) profit sharing plan that provides retirement benefit to substantially all full-time U.S. employees. Eligible employees may contribute a percentage of their annual compensation, subject to Internal Revenue Service limitations, with the Company matching a portion of the employee’s contributions at the discretion of the Company. Matching contributions totaled $138,000 and $122,000 for the years ended December 31, 2017 and 2016, respectively. Inventory Purchase Commitments In connection with the acquisition of the Aquadex Business, the Company entered into a manufacturing and supply agreement with Baxter that was to expire within a period not to exceed 18 months from the close of the transaction. In May 2017, the Company notified Baxter to cease the manufacturing of the Aquadex product line as of June 30, 2017. In connection with this notification, the Company agreed to purchase the remaining Aquadex inventory, which consists mainly of raw materials priced at cost, through February 2018, for a total of $2.4 million. As of December 31, 2017, the Company had purchased and paid $1.2 million of this inventory and $1.2 million remained to be purchased. Contingent Consideration As described on Note 2, the Company agreed that if it disposes of any of the Aquadex assets for a price that exceeds $4.0 million within three years of the closing, it will pay Baxter 40% of the amount of such excess. In addition, it also agreed that if shares of its common stock cease to be publicly traded on Nasdaq, Baxter has the option to require the Company to repurchase, in cash, all or any part of the common shares held by Baxter at a price equal to their fair market value, as determined by a third-party appraiser.

Nature of Business and Significant Accounting Policies (FY) (Policies)

9 Months Ended

12 Months Ended

Sep. 30, 2018

Dec. 31, 2017

Going Concern

The Company became a revenue generating company after acquiring the Aquadex Business in August 2016. The Company expects to incur additional losses in the near-term as it grows the Aquadex Business, including investments in expanding its sales and marketing capabilities, purchasing inventory, manufacturing components, and complying with the requirements related to being a U.S. public company. To become and remain profitable, the Company must succeed in expanding the adoption and market acceptance of the Aquadex FlexFlow. This will require the Company to succeed in training personnel at hospitals and effectively and efficiently manufacturing, marketing and distributing the Aquadex FlexFlow and related components. There can be no assurance that the Company will succeed in these activities, and it may never generate revenues sufficient to achieve profitability.

Basis of Presentation

Use of Estimates

Cash and Cash Equivalents

Accounts Receivable

Inventories

(in thousands)	September 30, 2018		December 31, 2017
Finished Goods	$	810	$	902
Work in Process		91		217
Raw Materials		1,047		469
Total	$	1,948	$	1,588

Inventories

Inventories are recorded as the lower of cost or market using the first-in, first out method. Inventories consisted of the following as of December 31 (in thousands):

	2017		2016
Finished Goods	$	902	$	644
Work in Process		217		—
Raw Materials		469		33
Total	$	1,588	$	677

Other Current Assets

Other current assets represent prepayments and deposits made by the Company.

Property, Plant and Equipment

Office furniture and equipment	5-15 years
Computer software and equipment	3-4 years
Laboratory and research equipment	3-15 years
Production equipment	3-7 years
Leasehold improvements and capital lease asset	3-5 years

Depreciation expense was $229,000 and $419,000 for the years ended December 31, 2017, and 2016, respectively.

Intangible Assets

Intangible assets

Amortization expense was $540,000 and $278,000 for the years ended December 31, 2017 and 2016, respectively.

Goodwill

Contingent Consideration

Contingent consideration

Common Stock Warrant Liability

Common stock warrant liability

Revenue Recognition

Foreign Currency Translation

Stock-Based Compensation

See Note 7- Stock Based Compensation, for further information regarding the assumptions used to calculate the fair value of share-based compensation.

Income Taxes

Loss per Share

	September 30
	2018		2017
Stock options		1,987,502		36,874
Restricted stock units		90		324
Warrants to purchase common stock		8,522,672		496,629
Series F convertible preferred stock		266,680		-
Total		10,776,944		533,827

The following table reconciles reported net loss with reported net loss per share for the periods ended September 30, 2017:

(in thousands, except per share amounts)	Three months			Nine Months
Net loss	$	(2,847	)	$	(6,245	)
Deemed dividend to preferred shareholders (see Note 4)		-			(2,851	)
Net loss after deemed dividend		(2,847	)		(9,096	)
Weighted average shares outstanding		626			359
Basic and diluted loss per share	$	(4.55	)	$	(25.36	)

Loss per share

	December 31,
	2017		2016
Stock options		36,362		4,354
Restricted stock units		245		499
Warrants to purchase common stock		8,522,684		44,268
Series B, C and D convertible preferred stock		—		53,179
Series F convertible preferred stock		842,940		—-
Total		9,402,231		102,300

The following table reconciles reported net loss with reported net loss per share for the years ended December 31:

(in thousands, except per share amounts)	2017			2016
Net loss	$	(13,382	)	$	(15,792	)
Deemed dividend to preferred shareholders (see Note 6)		(11,590	)		(1,900	)
Net loss after deemed dividend		(24,972	)		(17,692	)
Weighted average shares outstanding		665			33
Basic and diluted loss per share	$	(37.51	)	$	(536.12	)

Research and Development

Reclassification

Recent Accounting Pronouncements

The Company evaluates events through the date the consolidated financial statements are filed for events requiring adjustment to or disclosure in the consolidated financial statements.

Nature of Business and Basis of Presentation (Q3) (Policies)

9 Months Ended

12 Months Ended

Sep. 30, 2018

Dec. 31, 2017

Nature of Business and Significant Accounting Policies [Abstract]

Principles of Consolidation

For further information, refer to the consolidated financial statements and notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2017.

Going Concern

The Company became a revenue generating company after acquiring the Aquadex Business in August 2016. The Company expects to incur additional losses in the near-term as it grows the Aquadex Business, including investments in expanding its sales and marketing capabilities, purchasing inventory, manufacturing components, and complying with the requirements related to being a U.S. public company. To become and remain profitable, the Company must succeed in expanding the adoption and market acceptance of the Aquadex FlexFlow. This will require the Company to succeed in training personnel at hospitals and effectively and efficiently manufacturing, marketing and distributing the Aquadex FlexFlow and related components. There can be no assurance that the Company will succeed in these activities, and it may never generate revenues sufficient to achieve profitability.

Revenue Recognition

Accounts Receivable

Inventories

(in thousands)	September 30, 2018		December 31, 2017
Finished Goods	$	810	$	902
Work in Process		91		217
Raw Materials		1,047		469
Total	$	1,948	$	1,588

Inventories

Inventories are recorded as the lower of cost or market using the first-in, first out method. Inventories consisted of the following as of December 31 (in thousands):

	2017		2016
Finished Goods	$	902	$	644
Work in Process		217		—
Raw Materials		469		33
Total	$	1,588	$	677

Contingent Consideration

Contingent consideration

Loss per Share

	September 30
	2018		2017
Stock options		1,987,502		36,874
Restricted stock units		90		324
Warrants to purchase common stock		8,522,672		496,629
Series F convertible preferred stock		266,680		-
Total		10,776,944		533,827

The following table reconciles reported net loss with reported net loss per share for the periods ended September 30, 2017:

(in thousands, except per share amounts)	Three months			Nine Months
Net loss	$	(2,847	)	$	(6,245	)
Deemed dividend to preferred shareholders (see Note 4)		-			(2,851	)
Net loss after deemed dividend		(2,847	)		(9,096	)
Weighted average shares outstanding		626			359
Basic and diluted loss per share	$	(4.55	)	$	(25.36	)

Loss per share

	December 31,
	2017		2016
Stock options		36,362		4,354
Restricted stock units		245		499
Warrants to purchase common stock		8,522,684		44,268
Series B, C and D convertible preferred stock		—		53,179
Series F convertible preferred stock		842,940		—-
Total		9,402,231		102,300

The following table reconciles reported net loss with reported net loss per share for the years ended December 31:

(in thousands, except per share amounts)	2017			2016
Net loss	$	(13,382	)	$	(15,792	)
Deemed dividend to preferred shareholders (see Note 6)		(11,590	)		(1,900	)
Net loss after deemed dividend		(24,972	)		(17,692	)
Weighted average shares outstanding		665			33
Basic and diluted loss per share	$	(37.51	)	$	(536.12	)

New Accounting Pronouncements

Recent Accounting Pronouncements

The Company evaluates events through the date the consolidated financial statements are filed for events requiring adjustment to or disclosure in the consolidated financial statements.

Nature of Business and Significant Accounting Policies [Abstract]

Disclosure of accounting policy for trade and other accounts receivables. This disclosure may include the basis at which such receivables are carried in the entity's statements of financial position (for example, net realizable value), how the entity determines the level of its allowance for doubtful accounts, when impairments, charge-offs or recoveries are recognized, and the entity's income recognition policies for such receivables, including its treatment of related fees and costs, its treatment of premiums, discounts or unearned income, when accrual of interest is discontinued, how the entity records payments received on nonaccrual receivables and its policy for resuming accrual of interest on such receivables. If the enterprise holds a large number of similar loans, disclosure may include the accounting policy for the anticipation of prepayments and significant assumptions underlying prepayment estimates for amortization of premiums, discounts, and nonrefundable fees and costs.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Section S99
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-Subparagraph (SX 210.7-03(a)(5))
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 7: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 8: http://fasb.org/us-gaap/role/ref/legacyRef
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-URI http://asc.fasb.org/extlink&oid=84158767&loc=d3e18780-107790

Reference 9: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Subparagraph (SX 210.5-02(4))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Nature of Business and Significant Accounting Policies (FY) (Tables)

9 Months Ended

12 Months Ended

Sep. 30, 2018

Dec. 31, 2017

Schedule of Inventories

Inventories consisted of the following:

(in thousands)	September 30, 2018		December 31, 2017
Finished Goods	$	810	$	902
Work in Process		91		217
Raw Materials		1,047		469
Total	$	1,948	$	1,588

Inventories are recorded as the lower of cost or market using the first-in, first out method. Inventories consisted of the following as of December 31 (in thousands):

	2017		2016
Finished Goods	$	902	$	644
Work in Process		217		—
Raw Materials		469		33
Total	$	1,588	$	677

Summary of Estimated Useful Lives

Depreciation expense has been calculated using the following estimated useful lives:

Office furniture and equipment	5-15 years
Computer software and equipment	3-4 years
Laboratory and research equipment	3-15 years
Production equipment	3-7 years
Leasehold improvements and capital lease asset	3-5 years

Potential Shares of Common Stock not Included in Diluted Net Loss Per Share

	September 30
	2018		2017
Stock options		1,987,502		36,874
Restricted stock units		90		324
Warrants to purchase common stock		8,522,672		496,629
Series F convertible preferred stock		266,680		-
Total		10,776,944		533,827

	December 31,
	2017		2016
Stock options		36,362		4,354
Restricted stock units		245		499
Warrants to purchase common stock		8,522,684		44,268
Series B, C and D convertible preferred stock		—		53,179
Series F convertible preferred stock		842,940		—-
Total		9,402,231		102,300

Schedule of Reconciles Reported Net Loss with Reported Net Loss Per Share

The following table reconciles reported net loss with reported net loss per share for the periods ended September 30, 2017:

(in thousands, except per share amounts)	Three months			Nine Months
Net loss	$	(2,847	)	$	(6,245	)
Deemed dividend to preferred shareholders (see Note 4)		-			(2,851	)
Net loss after deemed dividend		(2,847	)		(9,096	)
Weighted average shares outstanding		626			359
Basic and diluted loss per share	$	(4.55	)	$	(25.36	)

The following table reconciles reported net loss with reported net loss per share for the years ended December 31:

(in thousands, except per share amounts)	2017			2016
Net loss	$	(13,382	)	$	(15,792	)
Deemed dividend to preferred shareholders (see Note 6)		(11,590	)		(1,900	)
Net loss after deemed dividend		(24,972	)		(17,692	)
Weighted average shares outstanding		665			33
Basic and diluted loss per share	$	(37.51	)	$	(536.12	)

Aquadex Acquisition (FY) (Tables)

12 Months Ended

Dec. 31, 2017

Aquadex Acquisition [Abstract]

Purchase Consideration for Business

Purchase Consideration: Total purchase consideration for the Aquadex Business was as follows:

(in thousands)
Cash consideration	$	4,000
Common stock consideration		950
Fair value of contingent consideration		126
Total purchase consideration	$	5,076

Amount Recognized for Assets Acquired

Capital lease asset	$	307
Intangible assets		4,580
Total identifiable assets acquired		4,887
Goodwill		189
Total purchase consideration	$	5,076

Summary of Pro Forma Information

Twelve months ended December 31, 2016 (in thousands, except share amounts)
Pro forma net sales	$	3,160
Pro forma net loss from operations		(15,340	)
Pro forma basic and diluted net loss per share	$	(464.84	)

Property, Plant and Equipment (FY) (Tables)

12 Months Ended

Dec. 31, 2017

Property, Plant and Equipment [Abstract]

Summary of Property, Plant and Equipment

Property, plant and equipment were as follows:

(in thousands)	December 31, 2017			December 31, 2016
Office Furniture & Fixtures	$	287		$	280
Leasehold Improvements		224			145
Software		129			124
Production Equipment		926			968
Computer Equipment		277			245
Capital Lease Asset		307			307
Total		2,150			2,069
Accumulated Depreciation		(1,580	)		(1,529	)
	$	570		$	540

Intangible Assets (FY) (Tables)

12 Months Ended

Dec. 31, 2017

Intangible Assets [Abstract]

Summary of Intangible Assets

Intangible assets were as follows:

(in thousands)	December 31, 2017			December 31, 2016
Customer Relationships	$	3,090		$	3,090
Developed Technology		1,050			1,050
Trade Names and Trademarks		440			440
Total		4,580			4,580
Accumulated Amortization		(818	)		(278	)
Impairment Charge		(3,762	)		—
	$	—		$	4,302

Stock-Based Compensation (FY) (Tables)

9 Months Ended

12 Months Ended

Sep. 30, 2018

Dec. 31, 2017

Summary of Stock-Based Compensation Expense

The following table presents the classification of stock-based compensation expense recognized for the periods below:

	Three months ended September 30,					Nine months ended September 30,
(in thousands)	2018			2017		2018		2017
Selling, general and administrative expense	$	440		$	106	$	1,446	$	351
Research and development expense		(3	)		5		98		43
Total stock-based compensation expense	$	437		$	111	$	1,544	$	394

The following table summarizes the stock-based compensation expense which was recognized in the consolidated statements of operations for the years ended December 31,

(Dollars in thousands)	2017		2016
Selling, general and administrative	$	452	$	630
Research and development		50		385
Total	$	502	$	1,015

Summary of Plan Stock Option Activity

The following is a summary of the Plans’ stock option activity during the years ended December 31:

	2017					2016
	Options Outstanding			Weighted Average Exercise Price		Options Outstanding			Weighted Average Exercise Price
Beginning Balance		4,354		$	2,295.37		3,260		$	3,664.61
Granted		34,651		$	11.57		2,257		$	543.63
Exercised		—			—		—			—
Forfeited/expired		(2,643	)	$	2,666.48		(1,163	)	$	2,729.60
Outstanding at December 31		36,362		$	91.48		4,354		$	2,295.37
Vested at December 31		2,344		$	964.27		2,134		$	3,780.79

Schedule of Weighted Average Assumptions used in Black-Scholes Option Pricing Model

The following table provides the weighed average assumptions used in the Black-Scholes option pricing model for the years ended December 31:

	2017			2016
Expected dividend yield		0	%		0	%
Risk-free interest rate		1.97	%		1.71	%
Expected volatility		103	%		86	%
Expected life (in years)		6.25			6.25

Summary of Restricted Stock Award Activity

The following table summarizes restricted stock award activity during 2017 and 2016:

	2017					2016
	RSUs			Weighted Average Grant Price		RSUs			Weighted Average Grant Price
Nonvested, beginning balance		499		$	583.29		15		$	2,574.00
Granted		138		$	108.20		1,131		$	553.88
Vested		(392	)	$	132.70		(619	)	$	443.40
Forfeited		—			—		(28	)	$	426.00
Nonvested at December 31		245		$	521.23		499		$	583.29

Fair Value of Financial Instruments (FY) (Tables)

9 Months Ended

12 Months Ended

Sep. 30, 2018

Dec. 31, 2017

Fair Value of Common Stock Warrant Liability Calculated Using a Monte Carlo Valuation Model Classified as Level 3 in Fair Value Hierarchy

The following is a rollforward of the fair value of Level 3 warrants:

Nine months ended September 30, 2017 (in thousands)
Balance December 31, 2016	$	1,843
Change in fair value		(1,469	)
Exercise of warrants		(368	)
Ending balance as of September 30, 2017	$	6

The following is a rollforward of the fair value of Level 3 warrants:

(in thousands)
July 26, 2016 warrant issuance	$	1,883
November 3, 2016 warrant issuance		778
Change in fair value		(818	)
Ending balance December 31, 2016		1,843
Change in fair value		(1,475	)
Exercise of warrants		(368	)
Ending balance as of December 31, 2017	$	—

Summary of Fair Value Assumptions Used in Calculation of Monte Carlo Valuation Model

Fair values were calculated using the following assumptions:

	As of Dec. 31, 2016			As of date of exercise
Risk-free interest rates, adjusted for continuous compounding		1.47/1.96	%		1.45-1.99	%
Term (years)		3.1/5.3			2.84-5.50
Expected volatility		55.3/49.8	%		49.9-58.5	%
Dates and probability of future equity raises	various			various

Fair values were calculated using the following assumptions:

	July 26, 2016			Nov. 3, 2016			Dec. 31, 2016
Risk-free interest rates, adjusted for continuous compounding		0.94	%		1.33	%		1.47/1.96	%
Term (years)		3.5			5.5			3.1/5.3
Expected volatility		78	%		41.4	%		55.3/49.8	%
Dates and probability of future equity raises		various			various			various

Income Taxes (FY) (Tables)

12 Months Ended

Dec. 31, 2017

Income Taxes [Abstract]

Summary of Domestic and Foreign Loss Before Income Taxes

Domestic and foreign loss before income taxes, consists of the following for the years ended December 31:

(in thousands)	2017			2016
Domestic	$	(13,367	)	$	(15,877	)
Foreign		(9	)		31
Loss before income taxes	$	(13,376	)	$	(15,846	)

Summary of Components of Income Tax Benefit (Expense)

The components of income tax benefit (expense) consist of the following for the years ended December 31:

(in thousands)	2017			2016
Current:
United States and state	$	—		$	—
Foreign, net		(6	)		54
Deferred:
United States and state		—			—
Foreign		—			—
Total income tax benefit (expense)	$	(6	)	$	54

Summary of Actual Income Tax Benefit (Expense) Differs from Statutory Federal Income Tax Benefit (Expense)

Actual income tax benefit (expense) differs from statutory federal income tax benefit (expense) as follows for the years ended December 31:

(in thousands)	2017			2016
Statutory federal income tax benefit	$	4,548		$	5,388
State tax benefit, net of federal taxes		48			2
Foreign tax		—			3
R&D tax credit		—			80
Foreign deferred exchange rate adjustments		899			—
Nondeductible/nontaxable items		(114	)		(86	)
New federal rate adjustment		(16,081	)		—
Other		(1,085	)		(257	)
Valuation allowance decrease (increase)		11,779			(5,076	)
Total income tax benefit (expense)	$	(6	)	$	54

Summary of Components of Deferred Taxes

Deferred taxes consist of the following as of December 31:

(in thousands)	2017			2016
Deferred tax assets:
Noncurrent:
Accrued leave	$	32		$	43
Other accrued expenses		28			97
Stock based compensation		336			1,477
Net operating loss carryforward		38,947			49,720
Deferred rent		7			17
Other		108			777
Intangibles		895
R&D credit carryforward		531			531
Total deferred tax assets	$	40,884		$	52,662
Less: valuation allowance		(40,884	)		(52,662	)
Total	$	—		$	—

Nature of Business and Basis of Presentation (Q3) (Tables)

9 Months Ended

12 Months Ended

Sep. 30, 2018

Dec. 31, 2017

Nature of Business and Significant Accounting Policies [Abstract]

Inventories

Inventories consisted of the following:

(in thousands)	September 30, 2018		December 31, 2017
Finished Goods	$	810	$	902
Work in Process		91		217
Raw Materials		1,047		469
Total	$	1,948	$	1,588

Inventories are recorded as the lower of cost or market using the first-in, first out method. Inventories consisted of the following as of December 31 (in thousands):

	2017		2016
Finished Goods	$	902	$	644
Work in Process		217		—
Raw Materials		469		33
Total	$	1,588	$	677

Potential Shares of Common Stock not Included in Diluted Net Loss Per Share

	September 30
	2018		2017
Stock options		1,987,502		36,874
Restricted stock units		90		324
Warrants to purchase common stock		8,522,672		496,629
Series F convertible preferred stock		266,680		-
Total		10,776,944		533,827

	December 31,
	2017		2016
Stock options		36,362		4,354
Restricted stock units		245		499
Warrants to purchase common stock		8,522,684		44,268
Series B, C and D convertible preferred stock		—		53,179
Series F convertible preferred stock		842,940		—-
Total		9,402,231		102,300

Reconciliation of Reported Net Loss with Reported Net Loss Per Share

The following table reconciles reported net loss with reported net loss per share for the periods ended September 30, 2017:

(in thousands, except per share amounts)	Three months			Nine Months
Net loss	$	(2,847	)	$	(6,245	)
Deemed dividend to preferred shareholders (see Note 4)		-			(2,851	)
Net loss after deemed dividend		(2,847	)		(9,096	)
Weighted average shares outstanding		626			359
Basic and diluted loss per share	$	(4.55	)	$	(25.36	)

The following table reconciles reported net loss with reported net loss per share for the years ended December 31:

(in thousands, except per share amounts)	2017			2016
Net loss	$	(13,382	)	$	(15,792	)
Deemed dividend to preferred shareholders (see Note 6)		(11,590	)		(1,900	)
Net loss after deemed dividend		(24,972	)		(17,692	)
Weighted average shares outstanding		665			33
Basic and diluted loss per share	$	(37.51	)	$	(536.12	)

Stock-Based Compensation (Q3) (Tables)

9 Months Ended

12 Months Ended

Sep. 30, 2018

Dec. 31, 2017

Classification of Stock-Based Compensation Expense

The following table presents the classification of stock-based compensation expense recognized for the periods below:

	Three months ended September 30,					Nine months ended September 30,
(in thousands)	2018			2017		2018		2017
Selling, general and administrative expense	$	440		$	106	$	1,446	$	351
Research and development expense		(3	)		5		98		43
Total stock-based compensation expense	$	437		$	111	$	1,544	$	394

The following table summarizes the stock-based compensation expense which was recognized in the consolidated statements of operations for the years ended December 31,

(Dollars in thousands)	2017		2016
Selling, general and administrative	$	452	$	630
Research and development		50		385
Total	$	502	$	1,015

Fair Value of Financial Instruments (Q3) (Tables)

9 Months Ended

12 Months Ended

Sep. 30, 2018

Dec. 31, 2017

Fair Value of Common Stock Warrant Liability Calculated Using a Monte Carlo Valuation Model Classified as Level 3 in Fair Value Hierarchy

The following is a rollforward of the fair value of Level 3 warrants:

Nine months ended September 30, 2017 (in thousands)
Balance December 31, 2016	$	1,843
Change in fair value		(1,469	)
Exercise of warrants		(368	)
Ending balance as of September 30, 2017	$	6

The following is a rollforward of the fair value of Level 3 warrants:

(in thousands)
July 26, 2016 warrant issuance	$	1,883
November 3, 2016 warrant issuance		778
Change in fair value		(818	)
Ending balance December 31, 2016		1,843
Change in fair value		(1,475	)
Exercise of warrants		(368	)
Ending balance as of December 31, 2017	$	—

Summary of Fair Value Assumptions Used in Calculation of Monte Carlo Valuation Model

Fair values were calculated using the following assumptions:

	As of Dec. 31, 2016			As of date of exercise
Risk-free interest rates, adjusted for continuous compounding		1.47/1.96	%		1.45-1.99	%
Term (years)		3.1/5.3			2.84-5.50
Expected volatility		55.3/49.8	%		49.9-58.5	%
Dates and probability of future equity raises	various			various

Fair values were calculated using the following assumptions:

	July 26, 2016			Nov. 3, 2016			Dec. 31, 2016
Risk-free interest rates, adjusted for continuous compounding		0.94	%		1.33	%		1.47/1.96	%
Term (years)		3.5			5.5			3.1/5.3
Expected volatility		78	%		41.4	%		55.3/49.8	%
Dates and probability of future equity raises		various			various			various

Nature of Business and Significant Accounting Policies, Nature of Business, Going Concern, Accounts Receivable and Inventory (FY) (Details)					1 Months Ended	9 Months Ended	12 Months Ended
	Nov. 27, 2017 USD ($)	Oct. 12, 2017	Apr. 24, 2017 USD ($)	Jan. 12, 2017	Mar. 31, 2016 Study	Sep. 30, 2018 USD ($)	Dec. 31, 2017 USD ($) StockSplit	Dec. 31, 2016 USD ($)
Nature of Business [Abstract]
Number of clinical studies for C-Pulse System \| Study					2
Number of reverse stock split \| StockSplit							2
Reverse stock split ratio		20		30
Going Concern [Abstract]
Retained earnings (accumulated deficit)						$ (195,132,000)	$ (182,356,000)	$ (168,974,000)
Net proceeds from issuance of convertible preferred stock	$ 16,200,000		$ 8,000,000
Accounts Receivable [Abstract]
Accounts receivables maximum credit period from invoice date						30 days	30 days
Allowance for doubtful accounts						$ 0	$ 0	0
Inventories [Abstract]
Finished Goods						810,000	902,000	644,000
Work in Process						91,000	217,000	0
Raw Materials						1,047,000	469,000	33,000
Total						$ 1,948,000	$ 1,588,000	$ 677,000

Nature of Business and Significant Accounting Policies, Property, Plant and Equipment (FY) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Property, Plant and Equipment [Abstract]
Depreciation expense	$ 229	$ 419
Impairment losses recognized	$ 0	$ 0
Office Furniture and Equipment [Member] \| Minimum [Member]
Property, Plant and Equipment [Abstract]
Estimated useful lives	5 years
Office Furniture and Equipment [Member] \| Maximum [Member]
Property, Plant and Equipment [Abstract]
Estimated useful lives	15 years
Computer Software and Equipment [Member] \| Minimum [Member]
Property, Plant and Equipment [Abstract]
Estimated useful lives	3 years
Computer Software and Equipment [Member] \| Maximum [Member]
Property, Plant and Equipment [Abstract]
Estimated useful lives	4 years
Laboratory and Research Equipment [Member] \| Minimum [Member]
Property, Plant and Equipment [Abstract]
Estimated useful lives	3 years
Laboratory and Research Equipment [Member] \| Maximum [Member]
Property, Plant and Equipment [Abstract]
Estimated useful lives	15 years
Production Equipment [Member] \| Minimum [Member]
Property, Plant and Equipment [Abstract]
Estimated useful lives	3 years
Production Equipment [Member] \| Maximum [Member]
Property, Plant and Equipment [Abstract]
Estimated useful lives	7 years
Leasehold Improvements and Capital Lease Asset [Member] \| Minimum [Member]
Property, Plant and Equipment [Abstract]
Estimated useful lives	3 years
Leasehold Improvements and Capital Lease Asset [Member] \| Maximum [Member]
Property, Plant and Equipment [Abstract]
Estimated useful lives	5 years

Nature of Business and Significant Accounting Policies, Intangible assets and Goodwill (FY) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Finite-Lived Intangible Assets [Line Items]
Impairment charges related to finite-lived intangible assets	$ 3,800,000
Overall discount rate	30.00%
Amortization expense	$ 540,000	$ 278,000
Goodwill [Abstract]
Goodwill impairment loss	$ 200,000
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated useful life	7 years
Overall discount rate	30.00%
Developed Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated useful life	7 years
Overall discount rate	30.00%
Trade Names and Trademarks [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated useful life	7 years
Overall discount rate	30.00%

Nature of Business and Significant Accounting Policies, Income Taxes and Loss Per Share (FY) (Details) - USD ($)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Line Items]
U.S. corporate income tax rate						34.00%
Percentage of valuation allowance on deferred tax assets						100.00%
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potential shares of common stock that are not included in the calculation of diluted net loss per share (in shares)			10,776,944	533,827		9,402,231	102,300
Reported net loss with reported net loss per share [Abstract]
Net loss	$ (4,241,000)	$ (2,847,000)	$ (12,776,000)	$ (6,245,000)		$ (13,382,000)	$ (15,792,000)
Deemed dividend to preferred shareholders		0		(2,851,000)		(11,590,000)	(1,900,000)
Net loss after deemed dividend		$ (2,847,000)		$ (9,096,000)		$ (24,972,000)	$ (17,692,000)
Weighted average shares outstanding (in shares)	6,987,000	626,000	5,171,000	359,000		665,000	33,000
Basic and diluted loss per share (in dollars per share)	$ (0.61)	$ (4.55)	$ (2.47)	$ (25.36)		$ (37.51)	$ (536.12)
Series E Convertible Preferred Stock [Member]
Reported net loss with reported net loss per share [Abstract]
Deemed dividend to preferred shareholders				$ 1,000,000		$ (1,000,000)
Series F Convertible Preferred Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potential shares of common stock that are not included in the calculation of diluted net loss per share (in shares)			266,680	0		842,940	0
Reported net loss with reported net loss per share [Abstract]
Deemed dividend to preferred shareholders						$ (8,700,000)
Series C and D Convertible Preferred Stock [Member]
Reported net loss with reported net loss per share [Abstract]
Deemed dividend to preferred shareholders				$ 1,800,000		(1,800,000)
Series B and B-1 Convertible Preferred Stock [Member]
Reported net loss with reported net loss per share [Abstract]
Deemed dividend to preferred shareholders						$ (1,900,000)	$ (1,900,000)
Series B, C And D Convertible Preferred Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potential shares of common stock that are not included in the calculation of diluted net loss per share (in shares)						0	53,179
Plan [Member]
Income Tax Disclosure [Line Items]
U.S. corporate income tax rate					21.00%
Stock Options [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potential shares of common stock that are not included in the calculation of diluted net loss per share (in shares)			1,987,502	36,874		36,362	4,354
Restricted Stock Units [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potential shares of common stock that are not included in the calculation of diluted net loss per share (in shares)			90	324		245	499
Warrants to Purchase Common Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potential shares of common stock that are not included in the calculation of diluted net loss per share (in shares)			8,522,672	496,629		8,522,684	44,268

Aquadex Acquisition (FY) (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended		9 Months Ended		12 Months Ended
	Aug. 05, 2016	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017	Dec. 31, 2016
Business Acquisition [Line Item]
Revenue		$ 1,363	$ 957	$ 3,499	$ 2,722	$ 3,553	$ 1,289
Amounts recognized for assets acquired [Abstract]
Goodwill						0	189
Aquadex Product Line [Member]
Business Acquisition [Line Item]
Revenue						$ 3,600	1,200
Total purchase consideration [Abstract]
Cash consideration	$ 4,000
Common stock consideration	950
Fair value of contingent consideration	126
Total purchase consideration	$ 5,076
Common stock issued in acquisition (in shares)	1,666
Closing market value (in dollars per share)	$ 570
Contingent consideration payable in excess of sale or disposal of business assets	40.00%			40.00%
Sale or disposal of business assets threshold for contingent consideration	$ 4,000			$ 4,000
Acquisition related expenses	900
Amounts recognized for assets acquired [Abstract]
Capital lease asset	307
Intangible assets	4,580
Total identifiable assets acquired	4,887
Goodwill	189
Total purchase consideration	$ 5,076
Pro forma information [Abstract]
Pro forma net sales							3,160
Pro forma net loss from operations							$ (15,340)
Pro forma basic and diluted net loss per share (in dollars per share)							$ (464.84)
Aquadex Product Line [Member] \| Maximum [Member]
Business Acquisition [Line Item]
Agreement term						18 months
Total purchase consideration [Abstract]
Contingent consideration period				3 years		3 years

Property, Plant and Equipment (FY) (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017	Dec. 31, 2016
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross		$ 2,150	$ 2,069
Accumulated Depreciation		(1,580)	(1,529)
Property, Plant and Equipment, Net	$ 573	570	540
Office Furniture & Fixtures [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross		287	280
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross		224	145
Software [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross		129	124
Production Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross		926	968
Computer Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross		277	245
Capital Lease Asset [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross		$ 307	$ 307

Intangible Assets (FY) (Details) - USD ($) $ in Thousands	12 Months Ended
Intangible Assets (FY) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Finite-Lived Intangible Assets [Line Items]
Intangible Assets, Gross	$ 4,580	$ 4,580
Accumulated Amortization	(818)	(278)
Impairment Charge	(3,762)	0
Intangible Assets, Net	$ 0	4,302
Discount rate	30.00%
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible Assets, Gross	$ 3,090	3,090
Discount rate	30.00%
Developed Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible Assets, Gross	$ 1,050	1,050
Discount rate	30.00%
Trade Names and Trademarks [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible Assets, Gross	$ 440	$ 440
Discount rate	30.00%

Debt, Prior Loan Agreement (FY) (Details) $ in Thousands					12 Months Ended
Debt, Prior Loan Agreement (FY) (Details) $ in Thousands	Aug. 04, 2016 USD ($)	Jan. 01, 2016 Installment	Jun. 26, 2015 USD ($)	Feb. 18, 2015 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Debt Instrument [Line Items]
Maximum borrowing capacity					$ 5,000
Repayment of outstanding debt					0	$ (8,000)
Loss on early retirement of long-term debt					0	(500)
Silicon Valley Bank [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity				$ 10,000
Annual interest rate				7.00%
Proceeds from term loan used for general corporate and working capital			$ 2,000	$ 6,000
Consecutive equal monthly installments \| Installment		24
Repayment of outstanding debt	$ (5,500)
Loss on early retirement of long-term debt	$ (500)
Total borrowings outstanding					$ 0	$ 0

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

Debt, Warrants (FY) (Details)	12 Months Ended
Debt, Warrants (FY) (Details)	Dec. 31, 2017 $ / shares shares	Sep. 30, 2018 $ / shares shares	Nov. 03, 2016	Jul. 26, 2016
Risk-Free Interest Rate [Member]
Debt Instrument [Line Items]
Warrants measurement input			0.0133	0.0094
Expected Warrant Option Life [Member]
Debt Instrument [Line Items]
Expected warrant option life			5 years 6 months	3 years 6 months
Affiliates [Member]
Debt Instrument [Line Items]
Warrants issued (in shares) \| shares	55	55
Exercise price of warrants (in dollars per share)	$ 2,208	$ 2,208
Value of warrants (in dollars per share)	$ 1,626	$ 1,626
Term of warrants	10 years
Affiliates [Member] \| Expected Dividend Yield [Member]
Debt Instrument [Line Items]
Warrants measurement input	0	0
Affiliates [Member] \| Expected Stock Price Volatility [Member]
Debt Instrument [Line Items]
Warrants measurement input	0.8704	0.8704
Affiliates [Member] \| Risk-Free Interest Rate [Member]
Debt Instrument [Line Items]
Warrants measurement input	0.0220	0.0220
Affiliates [Member] \| Expected Warrant Option Life [Member]
Debt Instrument [Line Items]
Expected warrant option life	6 years 3 months	6 years 3 months
Silicon Valley Bank [Member]
Debt Instrument [Line Items]
Warrants issued (in shares) \| shares	115	115
Exercise price of warrants (in dollars per share)	$ 3,132	$ 3,132
Value of warrants (in dollars per share)	$ 2,316	$ 2,316
Term of warrants	10 years
Silicon Valley Bank [Member] \| Expected Dividend Yield [Member]
Debt Instrument [Line Items]
Warrants measurement input	0	0
Silicon Valley Bank [Member] \| Expected Stock Price Volatility [Member]
Debt Instrument [Line Items]
Warrants measurement input	0.8807	0.8807
Silicon Valley Bank [Member] \| Risk-Free Interest Rate [Member]
Debt Instrument [Line Items]
Warrants measurement input	0.0186	0.0186
Silicon Valley Bank [Member] \| Expected Warrant Option Life [Member]
Debt Instrument [Line Items]
Expected warrant option life	6 years 3 months	6 years 3 months

Debt, New Loan Agreement (FY) (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2018	Dec. 31, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 5,000
Term Loan [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 4,000
Maturity date		Nov. 30, 2016
Revolving Line [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 1,000	$ 1,000
Maturity date	Mar. 31, 2020	Mar. 31, 2020
Total borrowings outstanding	$ 0	$ 0	$ 0
Revolving Line [Member] \| Floating Annual Rate [Member]
Debt Instrument [Line Items]
Interest rate	1.75%	1.75%
Revolving Line [Member] \| Prime Rate [Member]
Debt Instrument [Line Items]
Interest rate	1.00%	1.00%

Shareholder's Equity, Convertible Preferred Stock (FY) (Details) - USD ($)									3 Months Ended	9 Months Ended		12 Months Ended
	Jul. 03, 2018	Nov. 27, 2017	Apr. 24, 2017	Jan. 10, 2017	Nov. 03, 2016	Oct. 30, 2016	Jul. 26, 2016	Jul. 20, 2016	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017	Dec. 31, 2016
Class of Stock [Line Items]
Proceeds from issuance of convertible preferred stock and Warrants					$ 3,600,000	$ 3,800,000		$ 3,500,000
Net proceeds from issuance of convertible preferred stock		$ 16,200,000	$ 8,000,000
Preferred stock, shares outstanding (in shares)										0		0	0
Temporary equity												$ 0	$ 485,000
Net deemed dividend									$ 0		$ (2,851,000)	$ (11,590,000)	$ (1,900,000)
Common stock, shares issued (in shares)										7,074,407		3,798,929	38,862
Series B Convertible Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock, shares issued (in shares)							3,468
Number of preferred shares converted to common stock (in shares)							6,149
Conversion price (in dollars per share)							$ 564.0
Proceed from issuance of preferred stock							$ 1,600,000
Series B-1 Convertible Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock, shares issued (in shares)						2,227.2						0	1,824.4
Number of preferred shares converted to common stock (in shares)												17,866	3,948
Conversion price (in dollars per share)						$ 102
Number of convertible preferred shares converted (in shares)													402.8
Proceed from issuance of preferred stock						$ 1,600,000
Preferred stock, shares outstanding (in shares)												0	1,824.4
Series C Convertible Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock, shares issued (in shares)					2,900							0	2,900
Number of preferred shares converted to common stock (in shares)													0
Conversion price (in dollars per share)					$ 102
Preferred stock, shares outstanding (in shares)												0	2,900
Beneficial conversion amount				$ 1,300,000
Series D Convertible Preferred Stock [Member]
Class of Stock [Line Items]
Proceeds from issuance of convertible preferred stock and Warrants				$ 200,000
Preferred stock, shares issued (in shares)				200
Number of preferred shares converted to common stock (in shares)													0
Conversion price (in dollars per share)				$ 102	$ 102
Temporary stock, shares issued (in shares)					700							0	700
Beneficial conversion amount				$ 500,000
Temporary stock, shares outstanding (in shares)												0	700
Temporary equity													$ 485,000
Series C and D Convertible Preferred Stock [Member]
Class of Stock [Line Items]
Proceeds from issuance of convertible preferred stock and Warrants					$ 3,600,000
Number of preferred shares converted to common stock (in shares)												55,712
Preferred stock, shares outstanding (in shares)										0		0
Series B and B-1 Convertible Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock, shares outstanding (in shares)										0		0
Net deemed dividend												$ (1,900,000)	$ (1,900,000)
Series B, C And D Convertible Preferred Stock [Member]
Class of Stock [Line Items]
Percentage of placement fee offered in cash										6.00%		6.00%
Series E Convertible Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock, shares issued (in shares)			6,400									6,400
Number of preferred shares converted to common stock (in shares)			6,400,000									320,000
Proceed from issuance of preferred stock			$ 9,200,000
Net proceeds from issuance of convertible preferred stock			8,000,000
Preferred stock, shares outstanding (in shares)										0		0
Beneficial conversion amount			$ 1,000,000									$ 1,000,000
Percentage of placement fee offered in cash												9.00%
Net deemed dividend											$ 1,000,000	$ (1,000,000)
Common stock, shares issued (in shares)												140,000
Series E Convertible Preferred Stock [Member] \| Warrants [Member]
Class of Stock [Line Items]
Warrants to purchase shares of common stock (in shares)			9,200,000									640,000
Warrants issued to the placement agent (in shares)										0		0
Class A Units [Member]
Class of Stock [Line Items]
Public offering price (in dollars per share)												$ 20.00
Number of common stock (in shares)												1
Class A Units [Member] \| Warrants [Member]
Class of Stock [Line Items]
Number of preferred shares converted to common stock (in shares)												1
Term of warrants												5 years
Number of warrants (in shares)												1
Exercise price of warrants (in dollars per share)												$ 22
Class B Units [Member]
Class of Stock [Line Items]
Number of preferred shares converted to common stock (in shares)												50
Public offering price (in dollars per share)												$ 1,000
Number of preferred stock per unit (in shares)												1
Class B Units [Member] \| Warrants [Member]
Class of Stock [Line Items]
Warrants to purchase shares of common stock (in shares)												50
Exercise price of warrants (in dollars per share)												$ 22
Series F Convertible Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock, shares issued (in shares)		18,000								565		3,780	0
Number of preferred shares converted to common stock (in shares)	472	4,000,000								3,899,210		3,171,060
Conversion price (in dollars per share)	$ 2.12	$ 4.50
Number of convertible preferred shares converted (in shares)										17,435		14,220
Proceed from issuance of preferred stock		$ 18,000,000
Net proceeds from issuance of convertible preferred stock		16,200,000
Preferred stock, shares outstanding (in shares)										565		3,780	0
Beneficial conversion amount		$ 8,700,000
Percentage of placement fee offered in cash												8.00%
Net deemed dividend												$ (8,700,000)
Series F Convertible Preferred Stock [Member] \| Warrants [Member]
Class of Stock [Line Items]
Warrants to purchase shares of common stock (in shares)		8,000,000
Warrants issued to the placement agent (in shares)										0		0
Series F Convertible Preferred Stock [Member] \| Warrant Series 1 [Member]
Class of Stock [Line Items]
Number of preferred shares converted to common stock (in shares)		223
Exercise price of warrants (in dollars per share)		$ 4.50
Series F Convertible Preferred Stock [Member] \| Warrant Series 2 [Member]
Class of Stock [Line Items]
Number of preferred shares converted to common stock (in shares)		223
Exercise price of warrants (in dollars per share)		$ 4.50

Shareholder's Equity, Warrants (FY) (Details) $ / shares in Units, $ in Thousands				2 Months Ended	3 Months Ended		9 Months Ended		12 Months Ended
	Jan. 10, 2017 USD ($) $ / shares shares	Nov. 03, 2016 USD ($) $ / shares shares	Jul. 26, 2016 USD ($) $ / shares shares	Mar. 31, 2017 USD ($) $ / shares shares	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Feb. 15, 2017
Class of Stock [Line Items]
Proceeds from exercise of warrants							$ 0	$ 1,981	$ 1,989	$ 0
Warrants outstanding									0	1,843
Change in fair value of warrant liability					$ 0	$ 4	0	1,470	1,475	$ 818
Risk-Free Interest Rate [Member]
Class of Stock [Line Items]
Warrants measurement input		0.0133	0.0094
Risk-Free Interest Rate [Member] \| Minimum [Member]
Class of Stock [Line Items]
Warrants measurement input										0.0147	0.0145
Risk-Free Interest Rate [Member] \| Maximum [Member]
Class of Stock [Line Items]
Warrants measurement input										0.0196	0.0199
Expected Warrant Option Life [Member]
Class of Stock [Line Items]
Expected warrant option life		5 years 6 months	3 years 6 months
Expected Warrant Option Life [Member] \| Minimum [Member]
Class of Stock [Line Items]
Expected warrant option life										3 years 1 month 6 days	2 years 10 months 2 days
Expected Warrant Option Life [Member] \| Maximum [Member]
Class of Stock [Line Items]
Expected warrant option life										5 years 3 months 18 days	5 years 6 months
Replacement Warrants [Member]
Class of Stock [Line Items]
Warrants outstanding					$ 500		$ 500		$ 500
Replacement Warrants [Member] \| Expected Dividend Yield [Member]
Class of Stock [Line Items]
Warrants measurement input					0		0		0
Replacement Warrants [Member] \| Expected Stock Price Volatility [Member] \| Minimum [Member]
Class of Stock [Line Items]
Warrants measurement input					0.4965		0.4965		0.4965
Replacement Warrants [Member] \| Expected Stock Price Volatility [Member] \| Maximum [Member]
Class of Stock [Line Items]
Warrants measurement input					0.5038		0.5038		0.5038
Replacement Warrants [Member] \| Risk-Free Interest Rate [Member] \| Minimum [Member]
Class of Stock [Line Items]
Warrants measurement input					0.0195		0.0195		0.0195
Replacement Warrants [Member] \| Risk-Free Interest Rate [Member] \| Maximum [Member]
Class of Stock [Line Items]
Warrants measurement input					0.0197		0.0197		0.0197
Replacement Warrants [Member] \| Expected Warrant Option Life [Member]
Class of Stock [Line Items]
Expected warrant option life					5 years		5 years		5 years
Series B Convertible Preferred Stock [Member] \| Investor Warrants [Member]
Class of Stock [Line Items]
Warrants issuance cost			$ 0
Warrants to purchase shares of common stock (in shares) \| shares			6,149
Exercise price of warrants (in dollars per share) \| $ / shares			$ 564
Warrants exercisable period							36 months		36 months
Period warrants became exercisable from closing date							6 months		6 months
Series D Convertible Preferred Stock [Member] \| Investor Warrants [Member]
Class of Stock [Line Items]
Warrants issuance cost	$ 0
Warrants to purchase shares of common stock (in shares) \| shares	1,961
Exercise price of warrants (in dollars per share) \| $ / shares	$ 108
Warrants exercisable period							60 months		60 months
Period warrants became exercisable from closing date							6 months		6 months
Series C and D Convertible Preferred Stock [Member] \| Investor Warrants [Member]
Class of Stock [Line Items]
Warrants issuance cost		$ 0
Warrants to purchase shares of common stock (in shares) \| shares		35,295
Exercise price of warrants (in dollars per share) \| $ / shares		$ 108
Adjusted exercise price of warrants (in dollars per share) \| $ / shares		$ 102
Warrant Exercise Agreement [Member] \| Original Warrants [Member]
Class of Stock [Line Items]
Proceeds from exercise of warrants				$ 2,000
Warrants outstanding					$ 0		$ 0		$ 0
Relinquished amount of warrants								$ 100	$ 100
Warrant Exercise Agreement [Member] \| Replacement Warrants [Member]
Class of Stock [Line Items]
Warrants to purchase shares of common stock (in shares) \| shares				43,396
Warrant Exercise Agreement [Member] \| Replacement Warrants [Member] \| Minimum [Member]
Class of Stock [Line Items]
Exercise price of warrants (in dollars per share) \| $ / shares				$ 34.6
Warrant Exercise Agreement [Member] \| Replacement Warrants [Member] \| Maximum [Member]
Class of Stock [Line Items]
Exercise price of warrants (in dollars per share) \| $ / shares				$ 99.8

Stock-Based Compensation, Stock Options and Restricted Stock Awards (FY) (Details) - USD ($)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	$ 437,000	$ 111,000	$ 1,544,000	$ 394,000	$ 502,000	$ 1,015,000
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period					1 year
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period					4 years
Selling, General and Administrative [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	440,000	106,000	1,446,000	351,000	$ 452,000	630,000
Research and Development [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	$ (3,000)	$ 5,000	$ 98,000	$ 43,000	$ 50,000	$ 385,000
Stock Options [Member]
Share-based Payment Award, Options, Outstanding [Roll Forward]
Outstanding, beginning balance (in shares)			36,362	4,354	4,354	3,260
Granted (in shares)					34,651	2,257
Exercised (in shares)					0	0
Forfeited/expired (in shares)					(2,643)	(1,163)
Outstanding, ending balance (in shares)					36,362	4,354
Vested at the end of the year (in shares)					2,344	2,134
Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract]
Outstanding at the beginning of the year (in dollars per share)			$ 91.48	$ 2,295.37	$ 2,295.37	$ 3,664.61
Granted (in dollars per share)					11.57	543.63
Exercised (in dollars per share)					0	0
Forfeited/expired (in dollars per share)					2,666.48	2,729.60
Outstanding at the end of the year (in dollars per share)					91.48	2,295.37
Vested at the end of the year (in dollars per share)					$ 964.27	$ 3,780.79
Share Based Payment Award, Options Weighted Average Remaining Contractual Term [Abstract]
Options outstanding, weighted average remaining contractual life					9 years 3 months 29 days
Options vested, weighted average remaining contractual life					8 years 3 months 14 days
Share Based Payment Award, Aggregate Intrinsic Value [Abstract]
Fair value of options, vested					$ 700,000	$ 1,100,000
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]
Expected dividend yield					0.00%	0.00%
Risk-free interest rate					1.97%	1.71%
Expected volatility					103.00%	86.00%
Expected life					6 years 3 months	6 years 3 months
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Weighted-average fair value of options granted (in dollars per share)					$ 11.97	$ 543.63
Total unrecognized compensation costs related to non-vested stock option awards					$ 744,000
Unrecognized compensation costs related to non-vested stock option awards, recognition period					3 years 1 month 6 days
Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Nonvested beginning balance (in shares)			245	499	499	15
Granted (in shares)					138	1,131
Vested (in shares)					(392)	(619)
Forfeited (in shares)					0	(28)
Nonvested ending balance (in shares)					245	499
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Nonvested weighted average grant price beginning balance (in dollars per share)			$ 521.23	$ 583.29	$ 583.29	$ 2,574.00
Granted (in dollars per share)					108.20	553.88
Vested (in dollars per share)					132.70	443.40
Forfeited (in dollars per share)					0	426.00
Nonvested weighted average grant price ending balance (in dollars per share)					$ 521.23	$ 583.29
Employees tendered restricted stock units (in shares)					15	165

Stock-Based Compensation, Warrants (FY) (Details) - Warrants [Member] - $ / shares	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Class of Warrant or Right [Line Items]
Warrants outstanding (in shares)	8,522,684	44,268
Minimum [Member]
Class of Warrant or Right [Line Items]
Exercise price of warrants (in dollars per share)	$ 4.50
Warrants exercisable period	11 months
Maximum [Member]
Class of Warrant or Right [Line Items]
Exercise price of warrants (in dollars per share)	$ 383.57
Warrants exercisable period	7 years 6 months

Fair Value of Financial Instruments (FY) (Details) $ in Thousands			2 Months Ended	3 Months Ended		9 Months Ended		12 Months Ended
	Nov. 03, 2016 USD ($)	Jul. 26, 2016 USD ($)	Dec. 31, 2016 USD ($)	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Feb. 15, 2017
Fair value of Level 3 [Roll Forward]
Warrant issuance						$ 0	$ 509	$ 509	$ 0
Change in fair value				$ 0	$ 4	0	1,470	1,475	818
Ending balance			$ 1,843					0	1,843
Fair Value Transfers between levels [Abstract]
Level 1 to Level 2 Asset Transfers			0	0		0		0	0
Level 2 to Level 1 Asset Transfers			0	0		0		0	0
Level 1 to Level 2 Liability Transfers			0	0		0		0	0
Level 2 to Level 1 Liability Transfers			$ 0	$ 0		$ 0		0	$ 0
Risk-Free Interest Rates, Adjusted for Continuous Compounding [Member]
Fair Value Assumptions [Abstract]
Fair value assumptions measurement input	0.0133	0.0094
Risk-Free Interest Rates, Adjusted for Continuous Compounding [Member] \| Minimum [Member]
Fair Value Assumptions [Abstract]
Fair value assumptions measurement input			0.0147						0.0147	0.0145
Risk-Free Interest Rates, Adjusted for Continuous Compounding [Member] \| Maximum [Member]
Fair Value Assumptions [Abstract]
Fair value assumptions measurement input			0.0196						0.0196	0.0199
Term [Member]
Fair Value Assumptions [Abstract]
Term	5 years 6 months	3 years 6 months
Term [Member] \| Minimum [Member]
Fair Value Assumptions [Abstract]
Term			3 years 1 month 6 days						3 years 1 month 6 days	2 years 10 months 2 days
Term [Member] \| Maximum [Member]
Fair Value Assumptions [Abstract]
Term			5 years 3 months 18 days						5 years 3 months 18 days	5 years 6 months
Expected Volatility [Member]
Fair Value Assumptions [Abstract]
Fair value assumptions measurement input	0.4140	0.7800
Expected Volatility [Member] \| Minimum [Member]
Fair Value Assumptions [Abstract]
Fair value assumptions measurement input			0.498						0.498	0.499
Expected Volatility [Member] \| Maximum [Member]
Fair Value Assumptions [Abstract]
Fair value assumptions measurement input			0.5530						0.5530	0.585
Level 3 [Member]
Fair value of Level 3 [Roll Forward]
Change in fair value			$ (818)				(1,469)	(1,475)
Exercise of warrants							368	(368)
Ending balance			$ 1,843		$ 6		$ 6	$ 0	$ 1,843
Level 3 [Member] \| Warrants Issued July 26 2016 [Member]
Fair value of Level 3 [Roll Forward]
Warrant issuance		$ 1,883
Level 3 [Member] \| Warrants Issued November 3 2016 [Member]
Fair value of Level 3 [Roll Forward]
Warrant issuance	$ 778

Income Taxes, Domestic and Foreign Loss Before Income Taxes (FY) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017	Dec. 31, 2016
Loss before income taxes [Abstract]
Domestic					$ (13,367)	$ (15,877)
Foreign					(9)	31
Loss before income taxes	$ (4,240)	$ (2,842)	$ (12,773)	$ (6,239)	$ (13,376)	$ (15,846)

Income Taxes, Components of Income Tax Benefit (FY) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017	Dec. 31, 2016
Current [Abstract]
United States and state					$ 0	$ 0
Foreign, net					(6)	54
Deferred [Abstract]
United States and state					0	0
Foreign					0	0
Total income tax benefit (expense)	$ (1)	$ (5)	$ (3)	$ (6)	$ (6)	$ 54

Income Taxes, Effective Income Tax Rate Reconciliation (FY) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017	Dec. 31, 2016
Effective income tax rate reconciliation [Abstract]
Statutory federal income tax benefit					$ 4,548	$ 5,388
State tax benefit, net of federal taxes					48	2
Foreign tax					0	3
R&D tax credit					0	80
Foreign deferred exchange rate adjustments					899	0
Nondeductible/nontaxable items					(114)	(86)
New federal rate adjustment					(16,081)	0
Other					(1,085)	(257)
Valuation allowance decrease (increase)					11,779	(5,076)
Total income tax benefit (expense)	$ (1)	$ (5)	$ (3)	$ (6)	$ (6)	$ 54

Income Taxes, Deferred Taxes and Other Information (FY) (Details) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2017 AUD ($)	Dec. 31, 2016 AUD ($)
Noncurrent [Abstract]
Accrued leave		$ 32	$ 43
Other accrued expenses		28	97
Stock based compensation		336	1,477
Net operating loss carryforward		38,947	49,720
Deferred rent		7	17
Other		108	777
Intangibles		895
R&D credit carryforward		531	531
Total deferred tax assets		40,884	52,662
Less: valuation allowance		(40,884)	(52,662)
Total		$ 0	0
Income Tax Disclosure [Line Items]
U.S. corporate income tax rate		34.00%
Percentage of valuation allowance on deferred tax assets		100.00%
Operating Loss Carryforwards [Line Items]
Uncertain tax positions		$ 0	0
Interest and penalties related to uncertain tax positions accrued during the period		0	$ 0
Research Tax Credit Carryforward [Member] \| Australian Taxation Office [Member]
Tax Credit Carryforward [Line Items]
Fully refundable research and development tax credits				$ 0	$ 80
Plan [Member]
Income Tax Disclosure [Line Items]
U.S. corporate income tax rate	21.00%
United States [Member]
Operating Loss Carryforwards [Line Items]
Net operating loss (NOL) carryforwards		$ 120,200
Australian [Member]
Operating Loss Carryforwards [Line Items]
Net operating loss (NOL) carryforwards				$ 49,000

Commitments and Contingencies (FY) (Details) - USD ($)		9 Months Ended	12 Months Ended
Commitments and Contingencies (FY) (Details) - USD ($)	Aug. 05, 2016	Sep. 30, 2018	Dec. 31, 2017	Dec. 31, 2016	Jun. 30, 2017
Leases [Abstract]
Rent expense related to operating leases			$ 290,000	$ 286,000
Future minimum lease payments [Abstract]
2018			212,000
2019			60,000
2020			7,000
2021			0
2022			0
Employee Retirement Plan [Abstract]
Employer's matching contribution			138,000	$ 122,000
Aquadex Product Line [Member]
Inventory Purchase Commitments [Abstract]
Remaining inventory obligation			1,200,000		$ 2,400,000
Inventory purchases			$ 1,200,000
Contingent Consideration [Abstract]
Sale or disposal of business assets threshold for contingent consideration	$ 4,000,000	$ 4,000,000
Percentage of additional payments on disposal of business assets	40.00%	40.00%
Aquadex Product Line [Member] \| Maximum [Member]
Inventory Purchase Commitments [Abstract]
Agreement term			18 months
Contingent Consideration [Abstract]
Contingent consideration period		3 years	3 years

Segment and Geographic Information (FY) (Details)	12 Months Ended
Segment and Geographic Information (FY) (Details)	Dec. 31, 2017 Segment
Segment and Geographic Information [Abstract]
Number of reportable segments	1

Nature of Business and Basis of Presentation, Nature of Business, Going Concern, Accounts Receivable and Inventories (Q3) (Details) $ in Thousands			9 Months Ended		12 Months Ended		14 Months Ended
	Oct. 12, 2017	Jan. 12, 2017	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)	Dec. 31, 2017 USD ($) StockSplit	Dec. 31, 2016 USD ($)	Jul. 03, 2018 USD ($)
Nature of Business [Abstract]
Number of reverse stock split \| StockSplit					2
Reverse stock split ratio	20	30
Going Concern [Abstract]
Accumulated deficit			$ (195,132)		$ (182,356)	$ (168,974)
Net proceeds from public stock offering			$ 4,649	$ 8,002	$ 24,281	0	$ 28,800
Accounts Receivable [Abstract]
Accounts receivables maximum credit period from invoice date			30 days		30 days
Allowance for doubtful accounts			$ 0		$ 0	0
Inventories [Abstract]
Finished Goods			810		902	644
Work in Process			91		217	0
Raw Materials			1,047		469	33
Total			$ 1,948		$ 1,588	$ 677

Nature of Business and Basis of Presentation, Loss Per Share (Q3) (Details) - USD ($)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017	Dec. 31, 2016
Potential shares of common stock that are not included in the calculation of diluted net loss per share [Abstract]
Potential shares of common stock that are not included in the calculation of diluted net loss per share (in shares)			10,776,944	533,827	9,402,231	102,300
Reported net loss with reported net loss per share [Abstract]
Net loss	$ (4,241,000)	$ (2,847,000)	$ (12,776,000)	$ (6,245,000)	$ (13,382,000)	$ (15,792,000)
Deemed dividend to preferred shareholders		0		(2,851,000)	(11,590,000)	(1,900,000)
Net loss after deemed dividend		$ (2,847,000)		$ (9,096,000)	$ (24,972,000)	$ (17,692,000)
Weighted average shares outstanding (in shares)	6,987,000	626,000	5,171,000	359,000	665,000	33,000
Basic and diluted loss per share (in dollars per share)	$ (0.61)	$ (4.55)	$ (2.47)	$ (25.36)	$ (37.51)	$ (536.12)
Series C and D Convertible Preferred Stock [Member]
Reported net loss with reported net loss per share [Abstract]
Deemed dividend to preferred shareholders				$ 1,800,000	$ (1,800,000)
Series E Convertible Preferred Stock [Member]
Reported net loss with reported net loss per share [Abstract]
Deemed dividend to preferred shareholders				$ 1,000,000	$ (1,000,000)
Series F Convertible Preferred Stock [Member]
Potential shares of common stock that are not included in the calculation of diluted net loss per share [Abstract]
Potential shares of common stock that are not included in the calculation of diluted net loss per share (in shares)			266,680	0	842,940	0
Reported net loss with reported net loss per share [Abstract]
Deemed dividend to preferred shareholders					$ (8,700,000)
Stock Options [Member]
Potential shares of common stock that are not included in the calculation of diluted net loss per share [Abstract]
Potential shares of common stock that are not included in the calculation of diluted net loss per share (in shares)			1,987,502	36,874	36,362	4,354
Restricted Stock Units [Member]
Potential shares of common stock that are not included in the calculation of diluted net loss per share [Abstract]
Potential shares of common stock that are not included in the calculation of diluted net loss per share (in shares)			90	324	245	499
Warrants to Purchase Common Stock [Member]
Potential shares of common stock that are not included in the calculation of diluted net loss per share [Abstract]
Potential shares of common stock that are not included in the calculation of diluted net loss per share (in shares)			8,522,672	496,629	8,522,684	44,268

Revenue Recognition (Q3) (Details) - USD ($)	3 Months Ended	9 Months Ended
Revenue Recognition (Q3) (Details) - USD ($)	Sep. 30, 2018	Sep. 30, 2018	Dec. 31, 2017
Revenue, Performance Obligation [Abstract]
Deferred revenue	$ 41,250	$ 41,250	$ 38,000
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2018-07-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Expected timing of satisfaction, period	1 year	1 year
Sales Revenue [Member] \| Maximum [Member] \| ASC 606 [Member]
Revenue, Performance Obligation [Abstract]
Percentage of net sales	1.00%	1.00%

Debt, New Loan Agreement (Q3) (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2018	Dec. 31, 2017	Dec. 31, 2016
Line of Credit Facility [Abstract]
Maximum borrowing capacity		$ 5,000
Revolving Line [Member]
Line of Credit Facility [Abstract]
Maximum borrowing capacity	$ 1,000	$ 1,000
Maximum borrowing capacity percentage of eligible accounts	80.00%
Maturity date	Mar. 31, 2020	Mar. 31, 2020
Total borrowings outstanding	$ 0	$ 0	$ 0
Revolving Line [Member] \| Floating Annual Rate [Member]
Line of Credit Facility [Abstract]
Interest rate	1.75%	1.75%
Revolving Line [Member] \| Prime Rate [Member]
Line of Credit Facility [Abstract]
Interest rate	1.00%	1.00%