Warrants (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 31, 2019	Feb. 05, 2019
Warrants
Warrants outstanding (in warrants)	10,369,752
Warrant, equity component	$ 3,448
Dividend attributable to down round feature of warrants	$ 359
Penny Warrants
Warrants
Warrants outstanding (in warrants)	54,516
Exercise price (per warrant)	$ 0.01
2017 Warrants
Warrants
Warrants outstanding (in warrants)	2,758,094
Exercise price (per warrant)	$ 1.75	$ 6.085
2019 Warrants
Warrants
Warrants outstanding (in warrants)	7,557,142
Exercise price (per warrant)	$ 1.95	$ 1.95
Warrants (issued)		7,557,142

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

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- Definition

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

+ 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)(4))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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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.

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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

Number of warrants or rights outstanding.

+ 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))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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- Definition

Amount of (increase) decrease in equity for down round feature triggered for warrant classified as equity.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109259400&loc=SL109261905-112644

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 12B
-URI http://asc.fasb.org/extlink&oid=109260490&loc=SL109261756-109256

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