Consolidated Statements of Stockholders' Equity (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Common Stock and Warrants [Member]
Payment of offering costs		$ 690
Common Stock, Pre-funded Warrants and Warrants [Member]
Payment of offering costs		$ 1,630
Common Stock [Member]
Payment of offering costs	$ 234

The cash outflow for cost incurred directly with the issuance of an equity security.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3291-108585

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