Income Taxes (Income Tax Expense) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Current income tax expense	$ 59,530	$ 62,177	$ 49,736
Deferred income tax expense (benefit)	(19,059)	(4,130)	3,279
Income tax expense, as reported	$ 40,471	$ 58,047	$ 53,015