Common Stock - Summary of Outstanding Common Stock Warrants (Details) shares in Thousands	3 Months Ended
Mar. 31, 2020 $ / shares shares
Class Of Warrant Or Right [Line Items]
Warrants Outstanding	105
Exercise Price $19.55
Class Of Warrant Or Right [Line Items]
Warrants Outstanding	14
Exercise Price \| $ / shares	$ 19.55
Expiration Date	2022-12
Exercise Price $9.73
Class Of Warrant Or Right [Line Items]
Warrants Outstanding	30
Exercise Price \| $ / shares	$ 9.73
Expiration Date	2021-02
Exercise Price $9.73
Class Of Warrant Or Right [Line Items]
Warrants Outstanding	20
Exercise Price \| $ / shares	$ 9.73
Expiration Date	2023-08
Exercise Price $9.73
Class Of Warrant Or Right [Line Items]
Warrants Outstanding	20
Exercise Price \| $ / shares	$ 9.73
Expiration Date	2024-03
Exercise Price $9.73
Class Of Warrant Or Right [Line Items]
Warrants Outstanding	21
Exercise Price \| $ / shares	$ 9.73
Expiration Date	2024-12

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

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- Definition

The expiration, mandatory redemption, or due date, month and year (YYYY-MM), of the financial instrument issued in exchange for the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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