Leases - Maturity ASC 842 (Details) $ in Thousands	Mar. 31, 2019 USD ($)
Operating Leases
2019	$ 231,489
2020	308,607
2021	292,531
2022	289,447
2023	285,741
Thereafter	786,649
Total lease payments	2,194,464
Imputed interest and variable lease payments	(618,081)
Total lease obligations	1,576,383
Financing Leases
2019	66,190
2020	89,003
2021	90,243
2022	91,633
2023	93,104
Thereafter	428,952
Total lease payments	859,125
Purchase option liability and non-cash gain on future sale of property	575,276
Imputed interest and variable lease payments	(565,314)
Total lease obligations	$ 869,087