Commitments and Contingencies - Leases (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Operating Lease Liabilities, Payments Due [Abstract]
2019 (excluding the nine months ended September 30, 2019)	$ 4,297
2020	17,924
2021	18,608
2022	18,921
2023	18,107
Thereafter	1,168,805
Total lease payments	1,246,662
Less: Imputed interest	(990,495)
Present value of lease liabilities	$ 256,167
Operating And Capital Leases, Future Minimum Payments Due [Abstract]
2019		$ 18,882
2020		19,091
2021		19,223
2022		19,325
2023		19,429
Thereafter		1,219,303
Total		$ 1,315,253