Leases (Summary of Lease Assets and Liabilities) (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Leases [Abstract]
Operating lease asset	$ 119,774	$ 125,866
Finance lease asset	11,805	12,080
Total lease assets	131,579	137,946
Operating lease liability, current	34,424	32,929
Finance lease liability, current	3,952	3,667
Total lease liabilities, current	38,376	36,596
Operating lease liability, noncurrent	119,416	128,319
Finance lease liability, noncurrent	22,368	23,520
Total lease liabilities, noncurrent	141,784	151,839
Total lease liabilities	$ 180,160	$ 188,435
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	Property and equipment, net of accumulated depreciation of $299,737 and $286,133	Property and equipment, net of accumulated depreciation of $299,737 and $286,133
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	Operating and Finance Lease, Liability, Current	Operating and Finance Lease, Liability, Current
Finance Lease, Liability, Current, Statement of Financial Position [Extensible List]	Operating and Finance Lease, Liability, Current	Operating and Finance Lease, Liability, Current
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]	Total lease liabilities, noncurrent	Total lease liabilities, noncurrent
Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]	Total lease liabilities, noncurrent	Total lease liabilities, noncurrent