Leases (Supplemental Balance Sheet Information) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Leases [Abstract]
Right-of-use assets	$ 164,476	$ 193,311
Operating Lease, Liability, Statement of Financial Position [Extensible List]	us-gaap:OtherLiabilities	us-gaap:OtherLiabilities
Lease liabilities	$ 203,643	$ 230,338
Weighted-average remaining lease term	6 years 9 months 25 days	7 years 1 month 9 days
Weighted-average discount rate	5.94%	5.97%