Stockholders' Equity - Equity Issuances (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended		26 Months Ended
	Mar. 31, 2019	Feb. 28, 2018	Mar. 31, 2020	Aug. 31, 2018
Class of Stock [Line Items]
Aggregate market of common stock held by non-affiliates	$ 52.8
Lincoln Park Agreement
Class of Stock [Line Items]
Aggregate offering amount authorized per agreement	$ 26.0
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	$ 1.0
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	$ 2.5
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	$ 17.6			$ 25.0
Commission on gross proceeds due to third party (percent)		3.00%
Maximum number of shares authorized per agreement (in shares)	4,800,000
Stock issued (shares)			260,349
Proceeds from issuance of stock			$ 1.3