Stock-Based Compensation - Additional Information (Detail) (USD $)	3 Months Ended			0 Months Ended			0 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2014 Restricted Stock Units (RSUs)	Jun. 12, 2013 2008 Equity Incentive Plan	Jun. 06, 2012 2008 Equity Incentive Plan	Mar. 31, 2014 2008 Equity Incentive Plan	Jun. 06, 2012 Employee Stock Purchase Plan	Mar. 31, 2014 Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Increase in shares of common stock authorized for issuance				6,000,000	3,000,000		500,000
Maximum number of shares of common stock authorized for issuance				19,540,940			1,320,500
Number of shares available for future issuance	18,100,000					5,800,000		500,000
Outstanding options and other stock based awards	12,300,000
Restricted stock units vesting Description			The restricted stock units generally vest in three annual installments from the date of grant and are generally issuable at the end of the three-year vesting term.
Performance-based stock options awards	$ 0	$ 0
Performance-based stock options, outstanding	50,000