Leases - Maturity of Lease Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Jan. 01, 2019
Operating Leases
2019 (remaining nine months)	$ 41,736
2020	51,608
2021	41,414
2022	35,105
2023	31,996
After 2023	88,402
Total lease payments	290,261
Less: imputed interest	(41,305)
Present value of lease liabilities	$ 248,956	$ 256,400