Merger and Financing - Pre-Merger Financing (Details) - USD ($) shares in Millions, $ in Millions		1 Months Ended	12 Months Ended
	Oct. 04, 2019	Jun. 30, 2019	Dec. 31, 2019
Reverse Merger and Financing
Percentage of volume-weighted average trading price of a share of common stock that triggered release of converted additional shares (in percentage)	80.00%
Period over which trading price of common stock as quoted on the Nasdaq Capital Market was considered for the release of converted additional shares	3 days
Senior Secured Convertible Notes
Reverse Merger and Financing
Repayment of senior secured notes			$ 5.3
Series A and Series C warrants
Reverse Merger and Financing
Equity issuance cost			1.1
Series B Warrants
Reverse Merger and Financing
Equity issuance cost			0.8
Financing SPA
Reverse Merger and Financing
Number of shares agreed to issue immediately prior to the merger (in shares)		4.6
Number of converted initial shares, agreed to be issued (in shares)		2.2
Number of converted additional shares in the form of escrow agreed to issue immediately prior to the merger (in shares)		2.2
Aggregate purchase price		$ 25.0
Acquisition cost incurred		2.5
Equity issuance cost			1.9
Equity issuance costs paid in cash			0.7
Equity issuance costs paid with equity			$ 1.2
Net proceeds from pre-merger financing		$ 17.2