Income Tax Provision (Benefit) for Federal, and State and Local Income Taxes (Detail) - USD ($) $ in Thousands	3 Months Ended						6 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Jun. 30, 2014	Jun. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Current:
Current income tax expense, Federal											$ 1,511	$ 8,817	$ 31,109
Current income tax expense, State and local											1,500	1,524	575
Current income tax expense, Foreign											13,153	16,318	2,894
Total current											16,164	26,659	34,578
Deferred:
Deferred income tax expense, Federal											39,061	30,350	25,040
Deferred income tax expense, State and local											3,996	630	(655)
Deferred income tax expense, Foreign											423	436
Total deferred			$ 19,705			$ 7,001	$ 25,644	$ 8,412	$ 29,893	$ 15,246	43,474	31,416	24,385
Provision for income taxes	$ 9,856	$ 18,539	$ 25,527	$ 13,740	$ 18,661	$ 15,031	$ 44,066	$ 33,692	$ 53,922	$ 47,432	$ 59,641	$ 58,075	$ 58,963