Commitments and Contingencies - Narrative (Details) - USD ($)	3 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Lessee, Lease, Description [Line Items]
Minimum monthly rental expense	$ 4,000
Discount rate (as a percent)	12.00%
Right-of-use asset	$ 287,000	$ 0
Operating lease liability	300,000
Operating lease cost	$ 100,000
Remaining lease term	1 year
Remaining lease payments for remainder of fiscal year	$ 300,000
Building
Lessee, Lease, Description [Line Items]
Minimum monthly rental expense	$ 24,100
Annual rent increase (as a percent)	3.00%