Debt - Securities Purchase Agreement (Details)					1 Months Ended	3 Months Ended
	Aug. 02, 2018 USD ($)	Mar. 21, 2018 USD ($)	Feb. 26, 2018 USD ($)	Dec. 08, 2017 USD ($)	Mar. 31, 2019 USD ($)	Mar. 31, 2020 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2018 USD ($) NotesSeries item	Dec. 31, 2019 USD ($)
Debt
Proceeds from issuance of notes payable, net of issuance costs and debt discount						$ 350,000	$ 800,000
Number of notes for which standstill fee paid | NotesSeries								4
Standstill fee								$ 199,000
Increase in principal balance of notes payable								119,000
Standstill fee paid in cash								80,000
Loss on extinguishment of debt							(1,942,000)
Change in warrant liability						1,000	46,000
Chicago Venture Partners, L.P.
Debt
Total standstill fee								$ 499,000
Number of notes for which standstill fee paid | item								4
Securities purchase agreement | Chicago Venture Partners, L.P.
Debt
Principal amount		$ 1,090,000
Securities purchase agreement | Promissory Note, December 08, 2017 | Chicago Venture Partners, L.P.
Debt
Principal amount				$ 1,588,000
Aggregate purchase price				1,100,000
Original issue discount				462,500
Transaction expenses				$ 25,000
Interest rate (as a percent)				8.00%
Convertible debt payable					$ 862,000		862,000	$ 1,549,000
Maximum aggregate redemption amount	$ 500,000
Standstill fee								142,000
Increase in principal balance of notes payable								86,000
Standstill fee paid in cash								56,000
Repayments of notes payable, principal					811,000
Repayments of notes payable, interest					179,000
Loss on extinguishment of debt					243,000
Securities purchase agreement | February 2018 note payable | Chicago Venture Partners, L.P.
Debt
Principal amount			$ 2,241,000
Proceeds from issuance of notes payable, net of issuance costs and debt discount			1,560,000
Original issue discount			656,000
Transaction expenses			$ 25,000
Interest rate (as a percent)			8.00%
Repayments of notes payable, principal					2,045,000
Repayments of notes payable, interest					204,000
Loss on extinguishment of debt					$ 488,000			102,000
Carrying value of notes						$ 315,000			$ 2,291,000
Securities purchase agreement | March 2018 note payable
Debt
Discounts		315,000
Securities purchase agreement | March 2018 note payable | Chicago Venture Partners, L.P.
Debt
Aggregate purchase price		750,000
Transaction expenses		$ 25,000
Interest rate (as a percent)		8.00%
Standstill fee								96,000
Increase in principal balance of notes payable								58,000
Standstill fee paid in cash								38,000
Repayments of notes payable, principal							1,050,000
Repayments of notes payable, interest							86,000
Loss on extinguishment of debt							$ 1,211,000	224,000
Carrying value of notes								$ 1,006,000