Warrants - Summary of Shares Issuable Upon Exercise of Outstanding Warrants (Details) - $ / shares shares in Thousands	Dec. 31, 2019	Dec. 31, 2018
Class of Warrant or Right
Number of outstanding warrants (in shares)	39	39
Weighted-average exercise price per share (in dollars per share)	$ 5.88
Expiring between June 10, 2020 to July 9, 2020
Class of Warrant or Right
Number of outstanding warrants (in shares)	39	39
Weighted-average exercise price per share (in dollars per share)	$ 5.88

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

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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