Income Taxes - Expiry Dates of Federal and State Income Tax Credit Carryforwards (Detail) (USD $) In Thousands, unless otherwise specified					12 Months Ended			12 Months Ended			12 Months Ended			12 Months Ended		12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2013 Federal	Dec. 31, 2013 Federal U.S. foreign tax credit	Dec. 31, 2013 Federal U.S. foreign tax credit Minimum	Dec. 31, 2013 Federal U.S. foreign tax credit Maximum	Dec. 31, 2013 Federal U.S. research tax credit	Dec. 31, 2013 Federal U.S. research tax credit Minimum	Dec. 31, 2013 Federal U.S. research tax credit Maximum	Dec. 31, 2013 Federal U.S. business tax credits	Dec. 31, 2013 Federal U.S. business tax credits Minimum	Dec. 31, 2013 Federal U.S. business tax credits Maximum	Dec. 31, 2013 State	Dec. 31, 2012 State State investment tax credits	Dec. 31, 2013 State State investment tax credits	Dec. 31, 2012 State State research tax credits	Dec. 31, 2013 State State research tax credits
Tax Credit Carryforward [Line Items]
Tax credit carryforwards	$ 11,584	$ 6,024	$ 7,571	$ 4,102			$ 3,455			$ 14			$ 9,400		$ 872		$ 8,528
Tax credit carryforwards, expiration period														Do not expire		Do not expire
Tax credit carryforwards, expiration year					2020	2023		2030	2033		2030	2033