Operating Leases (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Lessee Lease Description [Line Items]
Operating lease right-of-use assets	$ 750,734	$ 793,181
Operating lease liabilities	$ 799,099	$ 839,800
Operating Lease, Liability, Statement of Financial Position [Extensible List]	Accounts payable and accrued expenses	Accounts payable and accrued expenses
Minimum [Member] | Office Space and Office Equipment [Member]
Lessee Lease Description [Line Items]
Operating leases remaining lease term	1 year
Maximum [Member] | Office Space and Office Equipment [Member]
Lessee Lease Description [Line Items]
Operating leases remaining lease term	14 years