Subsequent Events - Offering of Notes and Warrants (Details) - March 2019 Promissory notes - Securities purchase agreement - Subsequent event - USD ($) $ in Millions	Apr. 04, 2019	Mar. 18, 2019
Subsequent Events.
Aggregate principal amount		$ 5.5
Principal amount of Notes issued	$ 1.9

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(3)
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant