Leases (Lease Cost) (Detail) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2020	Dec. 31, 2019
Leases [Abstract]
Operating lease costs		$ 80,456	$ 120,201
Short-term lease cost ¹	[1]	6,544	2,897
Sublease income		(360)	(360)
Rental expense		86,640	122,738
Amortization of property and equipment		16,638	19,878
Interest expense		2,896	3,048
Total finance lease cost		19,534	22,926
Total operating and finance lease costs		$ 106,174	$ 145,664

[1] Short-term lease cost includes leases with a term of twelve months or less, as well as month-to-month leases and variable lease costs.