Income Taxes - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Components Of Income Before Taxes [Line Items]
Deferred tax expense (benefit) provision recorded as an adjustment to other comprehensive income	$ 400,000	$ 33,000
Foreign and domestic loss, unamortized research and development cost and state credit carry-forwards	19,000,000
Income tax benefit from exercise of stock options	169,000	1,905,000	10,525,000
Unrecognized tax benefits	3,240,000	2,926,000	2,970,000	2,593,000
Unrecognized tax benefits, effective tax rate	2,500,000	2,200,000	2,400,000
Accrued interest and penalties	$ 1,000,000	$ 800,000	$ 1,200,000
Minimum [Member]
Components Of Income Before Taxes [Line Items]
Operating loss carry forwards expiration year	2014
Maximum [Member]
Components Of Income Before Taxes [Line Items]
Operating loss carry forwards expiration year	2030