Leases - Supplemental Balance Sheet Information (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Operating leases
Operating lease right-of-use assets	$ 58,739	$ 69,872
Total operating lease liabilities	62,525	73,025
Financing leases
Financing lease right-of-use assets - related party	58,676	61,284
Total financing lease liabilities	61,351	62,517
Excluding Related Party
Operating leases
Operating lease right-of-use assets	33,947	53,344
Operating lease liabilities	30,182	43,135
Current portion of operating lease liabilities	6,474	11,874
Related Party
Operating leases
Operating lease right-of-use assets	24,792	16,528
Operating lease liabilities	23,049	15,469
Current portion of operating lease liabilities	2,820	2,547
Financing leases
Financing lease right-of-use assets - related party	58,676	61,284
Financing lease liabilities - related party	60,193	61,463
Current portion of financing lease liabilities - related party	$ 1,158	$ 1,054