Leases (Lease Cost) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Leases [Abstract]
Lease cost	$ 11,264	$ 11,236
Cash paid for amounts included in the measurement of lease liabilities reported in operating cash flows	11,377	10,830
Right-of-use assets obtained in exchange for new lease liabilities	$ 30	$ 1,612