Stockholders' Equity - Equity Issuances (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended				3 Months Ended		38 Months Ended
	Feb. 28, 2021	Jan. 31, 2021	Mar. 31, 2019	Aug. 31, 2018	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2021
Class of Stock [Line Items]
Aggregate market of common stock held by non-affiliates			$ 52,800
Net proceeds from issuance of common stock	$ 65,000				$ 85,457	$ 0
Shares issued upon exercise of warrants		801,148
Net proceeds from warrant exercises		$ 1,800
Lincoln Park Agreement
Class of Stock [Line Items]
Aggregate offering amount authorized per agreement			$ 26,000
Commitment shares issued as consideration per agreement (in shares)			181,510
Number of shares sold (in shares)			250,000
Price of shares sold (in dollars per share)			$ 4.00
Gross price for stock transaction			$ 1,000
Term of agreement (in months)			36 months
Number of shares allowable to direct for Regular Purchase (in shares)			100,000
Maximum obligation per directed purchase transaction for Regular Purchase			$ 2,500
Maximum shares allowed in Accelerated Purchase as percent of shares In Regular Purchase (percent)			300.00%
Maximum shares allowed in Accelerated Purchase as percent of shares traded during specified period (percent)			30.00%
Maximum beneficial ownership allowable per agreement (percent)			9.99%
H.C. Wainwright Sales Amended Agreement
Class of Stock [Line Items]
Aggregate offering amount authorized per agreement			$ 17,600	$ 25,000
Maximum number of shares authorized per agreement (in shares)			4,800,000
Commission on gross proceeds due to third party (percent)				3.00%
Stock issued (shares)							3,784,912
Net proceeds from issuance of common stock							$ 9,500
Institutional Purchase Agreement
Class of Stock [Line Items]
Number of shares sold (in shares)	24,906,134
Price of shares sold (in dollars per share)	$ 2.45
Number of shares called by warrants issued	12,453,067
Warrant exercise price (in dollars per share)	$ 2.90
Warrants expiration term	5 years
Additional Purchase Agreement
Class of Stock [Line Items]
Number of shares sold (in shares)	1,632,652
Price of shares sold (in dollars per share)	$ 2.45
Number of shares called by warrants issued	816,326
Warrant exercise price (in dollars per share)	$ 2.90
Warrants expiration term	5 years
January 2021 Private Placement
Class of Stock [Line Items]
Number of shares sold (in shares)		12,500,000
Price of shares sold (in dollars per share)		$ 2.00
Net proceeds from issuance of common stock		$ 25,000
Number of shares called by warrants issued		6,250,000
Warrant exercise price (in dollars per share)		$ 2.90
Warrants expiration term		5 years 6 months
Number of shares called by each warrant		1