Leases - Maturities of Operating Lease Liabilities (Details) $ in Thousands	Mar. 31, 2019 USD ($)
Operating Lease Liabilities, Payments Due [Abstract]
2019 (excluding the three months ended March 31, 2019)	$ 6,321
2020	8,290
2021	8,095
2022	6,278
2023	5,932
Thereafter	17,063
Total lease payments	51,979
Less imputed interest	(6,356)
Total operating liabilities	$ 45,623