Difference of Income Taxes from Statutory Federal Income Tax Rates (Detail)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Tax Disclosure [Abstract]
Federal U.S. income tax rate	35.00%	35.00%	35.00%
State income taxes, net of federal tax benefit	4.30%	4.00%	3.40%
Non-deductible expenses	0.70%	0.80%	1.30%
Non-U.S. income taxed at different rates, net of foreign tax credits	(1.00%)	0.70%	2.20%
Federal tax credits	(1.30%)	(0.30%)	(1.20%)
Tax impact of uncertain tax positions	0.10%	(1.20%)	(0.40%)
Valuation allowance release, net	(1.00%)
Other, net	(0.20%)		(0.20%)
Effective tax rate	36.60%	39.00%	40.10%