Income Taxes - Differences between Total Income Tax Expense and Income Tax Expense (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Tax Disclosure [Abstract]
Computed "expected" Federal income tax expense	$ 42,304	$ 45,614	$ 34,534
Increase (decrease) in income taxes resulting from:
State income taxes, net	3,138	5,551	4,200
Foreign non-taxed income, rate differential	(2,647)	(481)	(772)
Other adjustments, net	2,593	1,070	114
Total income tax expense (benefit)	$ 45,388	$ 51,754	$ 38,076