Leases - Supplemental Balance Sheet Information (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Leases [Abstract]
Accounts payable and accrued liabilities	$ 86,381	$ 83,995
Operating leases - liabilities	745,108	780,166
Total operating lease liabilities per the Condensed Consolidated Balance Sheets	$ 831,489	$ 864,161
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	Accounts payable and accrued liabilities	Accounts payable and accrued liabilities