Warrants - Aggregate Fair Values, Inputs and Assumptions (Details) $ in Thousands	Sep. 30, 2019 USD ($) $ / shares	Dec. 31, 2018 USD ($) $ / shares
Warrant
Fair value assumptions
Calculated aggregate value \| $	$ 3	$ 152
Weighted average exercise price per share \| Warrant
Fair value assumptions
Warrant liability, measurement input	22.50	22.50
Closing price per share of common stock \| Warrant
Fair value assumptions
Warrant liability, measurement input	2.96	1.50
Volatility \| Warrant
Fair value assumptions
Warrant liability, measurement input	0.967	0.941
Weighted average remaining expected life \| Warrant
Fair value assumptions
Weighted average remaining expected life	1 year 11 months	2 years 8 months
Risk-free interest rate \| Warrant
Fair value assumptions
Warrant liability, measurement input	0.0163	0.0245
Dividend yield
Fair value assumptions
Warrant liability, measurement input	0
Dividend yield \| Warrant
Fair value assumptions
Warrant liability, measurement input	0	0

It represents aggregate fair value of warrants.

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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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=117815213&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=117815213&loc=d3e19207-110258

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