Commitments and Contingencies - Narrative (Details) - USD ($)	3 Months Ended	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2019	Dec. 31, 2018
Lessee, Lease, Description [Line Items]
Right-of-use asset	$ 341,000	$ 341,000	$ 0
Current Headquarters
Lessee, Lease, Description [Line Items]
Minimum monthly rental expense		$ 4,000
Discount rate (as a percent)	12.00%	12.00%
Right-of-use asset	$ 300,000	$ 300,000
Operating lease liability	300,000	300,000
Operating lease cost	100,000	$ 300,000
Remaining lease term		1 year
Remaining lease payments for remainder of fiscal year	100,000	$ 100,000
Remaining lease payments in year two	300,000	300,000
Future Headquarters
Lessee, Lease, Description [Line Items]
Right-of-use asset	0	0
Operating lease liability	$ 0	0
Building | Current Headquarters
Lessee, Lease, Description [Line Items]
Minimum monthly rental expense		$ 24,100
Annual rent increase (as a percent)	3.00%	3.00%
Building | Future Headquarters
Lessee, Lease, Description [Line Items]
Minimum monthly rental expense		$ 3,800,000
Annual rent increase (as a percent)	3.00%	3.00%