Commitments and Contingencies - Schedule of Lease Costs and Weighted-Average Assumptions Used in Determining its Lease Assets and Lease Liabilities (Details) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2019 USD ($)	Sep. 30, 2019 USD ($)
Commitments And Contingencies Disclosure [Abstract]
Operating lease cost	$ 200	$ 501
Cash paid for operating leases	$ 200	508
Lease assets obtained in exchange for operating lease liabilities		$ 839
Weighted average remaining term for operating leases	7 months 28 days	7 months 28 days
Weighted average discount rate for operating leases	6.00%	6.00%