Off-Balance Sheet Arrangements Commitments Guarantees and Contingencies (Narrative) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Commitments And Guarantees [Line Items]
Credit card guarantees	$ 8,300	$ 7,900
Fully collateralized credit card guarantees	975	1,200
Rent expense for operating leases	30,200	30,600	$ 28,200
Aggregate future minimum rentals to be received under non-cancelable subleases greater than one year	468
Partnership Interest of a Director [Member]
Commitments And Guarantees [Line Items]
Rent expense for operating leases	$ 1,036	$ 963	$ 960