Subsequent Events - Proceeds from Sale of Common Stock (Details) - USD ($) $ in Thousands		2 Months Ended	12 Months Ended
	Mar. 04, 2019	Mar. 11, 2020	Dec. 31, 2019	Dec. 31, 2018
Subsequent Event [Line Items]
Stock issued (in shares)			1,535,848
Net proceeds from offering of common stock			$ 3,700
"At-The-Market" Equity Program
Subsequent Event [Line Items]
Stock issued (in shares)			532,700	0
"At-The-Market" Equity Program | Subsequent Events
Subsequent Event [Line Items]
Stock issued (in shares)		403,983
Net proceeds from offering of common stock		$ 600
Lincoln Park Capital Fund, LLC (“Investor”)
Subsequent Event [Line Items]
Stock issued (in shares)	269,749
Lincoln Park Capital Fund, LLC (“Investor”) | Subsequent Events
Subsequent Event [Line Items]
Stock issued (in shares)		450,000
Net proceeds from offering of common stock		$ 800