Stockholders' Equity - Additional Information (Detail) (USD $)	0 Months Ended	9 Months Ended
	Jun. 28, 2013	Sep. 30, 2014	Dec. 04, 2006	Sep. 30, 2014 ESPP [Member]	Sep. 30, 2014 Equity Incentive Plan [Member]	Jun. 27, 2014 Minimum [Member] Equity Incentive Plan [Member]	Jun. 27, 2014 Maximum [Member] Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum percentage before exercise			20.00%
Number of shares authorized for issuance				3,000,000		19,150,000	21,150,000
Number of shares available for issuance					2,800,000
Weighted-average grant-date fair value per share		$ 41.54
Employees share purchase plan, fair market value of common stock at beginning of offering period	85.00%	85.00%
Employees share purchase plan, fair market value of common stock at end of purchase period	85.00%	85.00%
Eligible employee contributions	$ 25,000	$ 25,000
Shares issued under the ESPP		90,067
Unrecognized stock-based compensation expense		$ 80,500,000
Unrecognized stock-based compensation expense, weighted-average period for recognition		2 years 4 months 24 days