Income Taxes - Schedule of Effective Income Tax Rate Reflected in Provision for Income Taxes and U.S. Federal Statutory Rate (Detail)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Disclosure [Abstract]
Federal income tax statutory rate	35.00%	35.00%	35.00%
Foreign income tax rate differential	(6.00%)	(6.00%)	(5.50%)
Foreign development tax incentive	(1.60%)	(2.60%)	(1.60%)
Manufacturing benefit	(1.70%)	(1.40%)	(1.20%)
Other	(0.40%)	(0.80%)	(0.30%)
Effective income tax rate	25.30%	24.20%	26.40%