Leases - Future Minimum Lease Payments (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Jan. 01, 2019
Leases [Abstract]
2019 (excluding the nine months ended September 30, 2019)	$ 30,078
2020	138,735
2021	143,833
2022	137,419
2023	132,865
Thereafter	634,742
Total future minimum lease payments	1,217,672
Less: Imputed interest	(317,805)
Operating lease liabilities	$ 899,867	$ 636,385