Value of stock issued as a result of the exercise of warrants.

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- Definition

Amount of liability recognized arising from contingent consideration in a business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
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- Definition

Amount of expense (income) related to adjustment to fair value of warrant liability.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
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- Definition

Amount of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Amount of transfers of assets measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

+ References

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Amount of transfers of liabilities measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

+ References

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- Definition

Amount of transfers of liabilities measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

+ References

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Value of outstanding derivative securities that permit the holder the right to purchase securities (usually equity) from the issuer at a specified price.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 235
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-Section S99
-Paragraph 1
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- Definition

Value of input used to measure outstanding warrant and right embodying unconditional obligation requiring redemption by transferring asset at specified or determinable date or upon event certain to occur.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

Period between issuance and expiration of outstanding warrant and right embodying unconditional obligation requiring redemption by transferring asset at specified or determinable date or upon event certain to occur, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-Name Accounting Standards Codification
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-SubTopic 10
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Fair Value of Financial Instruments (Q3) (Details) $ in Thousands	2 Months Ended	3 Months Ended		9 Months Ended		12 Months Ended
	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	Nov. 03, 2016	Jul. 26, 2016
Fair value of Level 3 [Roll Forward]
Balance				$ 0	$ 1,843	$ 1,843
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
Aquadex Product Line [Member]
Fair Value Transfers between levels [Abstract]
Fair value of contingent consideration		$ 126		126		126
Level 3 [Member]
Fair value of Level 3 [Roll Forward]
Balance				$ 0	1,843	1,843
Change in fair value	$ (818)				(1,469)	(1,475)
Exercise of warrants					(368)	368
Ending balance	$ 1,843		$ 6		$ 6	$ 0	$ 1,843