Income Tax Provision from Continuing Operations Resulted in Effective Tax Rates (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Income tax expense at federal statutory rate									$ 36,885	$ 35,494	$ 11,134
State income taxes, net of federal benefit									1,587	3,494	3,270
Benefit from lower foreign tax rates									(5,973)	(4,154)	(5,214)
Non-deductible goodwill impairment											29,313
Valuation allowance on foreign tax credits & net operating loss carryforward									2,326	4,604	8,206
Other expenses not deductible for tax purposes									2,719	2,962	2,872
Changes in non-taxable contingent consideration											(2,777)
Other adjustments, net									1,789	204	(4,399)
Income tax provision	$ 7,577	$ 6,177	$ 13,922	$ 11,657	$ 9,702	$ 12,329	$ 10,225	$ 10,348	$ 39,333	$ 42,604	$ 42,405