Income Taxes (Detail) - Current and Long-Term Deferred Tax Assets and Liabilities - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Accrued liabilities	$ 62,439	$ 67,888
Loss and credit carryforwards	7,766	8,522
Assets relating to equity compensation	25,569	22,686
Other assets	6,652	6,712
Gross deferred tax assets	102,426	105,808
Property, equipment, and leasehold improvements	(11,796)	(9,904)
Intangible assets	(43,548)	(55,275)
Prepaid expenses	(32,971)	(28,535)
Other liabilities	(7,925)	(7,244)
Gross deferred tax liabilities	(96,240)	(100,958)
Valuation allowance	(1,431)	(1,828)
Net deferred tax assets	$ 4,755	$ 3,022