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.

+ Details

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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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Warrants - Stock Warrants Outstanding (Details) - $ / shares	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Common Stock Warrants
Class of Warrant or Right [Line Items]
Number of Underlying Shares (in shares)	49,349
Exercise price (in usd per share)	$ 27.65	$ 27.65	$ 0.57
Expiration Date 2019 and 2020
Class of Warrant or Right [Line Items]
Number of Underlying Shares (in shares)	13,534
Exercise price (in usd per share)	$ 80.70
Expiration Date 2025
Class of Warrant or Right [Line Items]
Number of Underlying Shares (in shares)	11,718
Exercise price (in usd per share)	$ 8.53
Expiration Date 2024
Class of Warrant or Right [Line Items]
Number of Underlying Shares (in shares)	24,097
Exercise price (in usd per share)	$ 7.15