Equity - Issue and Conversion (Details) - USD ($)			1 Months Ended	3 Months Ended		12 Months Ended
	Apr. 01, 2019	May 09, 2018	Dec. 31, 2016	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2018	Jun. 07, 2018
Proceeds from issuance of common stock, net of issuance costs					$ 337,000
ATM Agreement
Aggregate value of securities allowed under agreement			$ 5,000,000
Aggregate securities allowed under agreement (in shares)			10,000,000
Common stock issued (in shares)					33,995
Sale price (in dollars per shares)					$ 0.34
Commission rate (as a percent)			2.00%
Proceeds from issuance of common stock, net of issuance costs					$ 11,000
Unamortized deferred cost					$ 136,000
LPC Program
Common stock issued (in shares)					1,213,642
Sale price (in dollars per shares)					$ 0.30
Commitment fee					$ 300,000
Amortization of deferred cost					35,000	$ 56,000
Proceeds from issuance of common stock, net of issuance costs					360,000
Equity issue costs					191,000
Unamortized deferred cost					$ 399,000	$ 434,000
Registered direct purchase agreement
Common stock issued (in shares)		3,153,808
Sale price (in dollars per shares)		$ 0.4122
Gross proceeds from common stock sale		$ 1,300,000
Commitment purchase agreement
Aggregate value of securities allowed under agreement		$ 10,000,000
Number of shares registered for resale under the Commitment Purchase Agreement							15,222,941
Subsequent Event
Proceeds from issuance of common stock, net of issuance costs				$ 100,000
Subsequent Event | LPC Program
Common stock issued (in shares)	375,000
Sale price (in dollars per shares)	$ 0.27
Proceeds from issuance of common stock, net of issuance costs	$ 100,000