Exercise price per share or per unit of warrants or rights outstanding.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(i)(4))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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- Definition

Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(i)(2))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

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- References

No definition available.

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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
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

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Debt, Warrants (Q3) (Details)	Sep. 30, 2018 $ / shares shares	Dec. 31, 2017 $ / shares shares	Nov. 03, 2016	Jul. 26, 2016
Risk-Free Interest Rate [Member]
Warrants and Rights Note Disclosure [Abstract]
Warrants measurement input			0.0133	0.0094
Expected Warrant Option Life [Member]
Warrants and Rights Note Disclosure [Abstract]
Expected warrant option life			5 years 6 months	3 years 6 months
Affiliates [Member]
Warrants and Rights Note Disclosure [Abstract]
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
Affiliates [Member] \| Expected Dividend Yield [Member]
Warrants and Rights Note Disclosure [Abstract]
Warrants measurement input	0	0
Affiliates [Member] \| Expected Stock Price Volatility [Member]
Warrants and Rights Note Disclosure [Abstract]
Warrants measurement input	0.8704	0.8704
Affiliates [Member] \| Risk-Free Interest Rate [Member]
Warrants and Rights Note Disclosure [Abstract]
Warrants measurement input	0.0220	0.0220
Affiliates [Member] \| Expected Warrant Option Life [Member]
Warrants and Rights Note Disclosure [Abstract]
Expected warrant option life	6 years 3 months	6 years 3 months
Silicon Valley Bank [Member]
Warrants and Rights Note Disclosure [Abstract]
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
Silicon Valley Bank [Member] \| Expected Dividend Yield [Member]
Warrants and Rights Note Disclosure [Abstract]
Warrants measurement input	0	0
Silicon Valley Bank [Member] \| Expected Stock Price Volatility [Member]
Warrants and Rights Note Disclosure [Abstract]
Warrants measurement input	0.8807	0.8807
Silicon Valley Bank [Member] \| Risk-Free Interest Rate [Member]
Warrants and Rights Note Disclosure [Abstract]
Warrants measurement input	0.0186	0.0186
Silicon Valley Bank [Member] \| Expected Warrant Option Life [Member]
Warrants and Rights Note Disclosure [Abstract]
Expected warrant option life	6 years 3 months	6 years 3 months