Leases - Reconciliation of the Undiscounted Cash Flows for Each of the First Five Years and Thereafter to Operating Lease Liabilities (Details) $ in Thousands	Sep. 30, 2019 USD ($)
Leases [Abstract]
2019 (remaining 3 months)	$ 1,190
2020	5,482
2021	5,493
2022	4,523
2023	2,306
Thereafter	3,366
Total lease payments	22,360
Less: imputed interest	(2,279)
Total lease liabilities	$ 20,081