Stock-Based Compensation - Stock Option Activity Under Equity Incentive Plans (Detail) - Stock Options [Member] $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2015 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Shares, Outstanding, Beginning balance | shares	21,995
Number of Shares, Options granted | shares	1,746
Number of Shares, Options exercised | shares	(3,937)
Number of Shares, Options forfeited and canceled | shares	(1,022)
Number of Shares, Outstanding, Ending balance | shares	18,782
Number of Shares, Vested and Expected to Vest | shares	18,360
Number of Shares, Exercisable | shares	12,222
Weighted-Average Exercise Price per Share, Outstanding, Beginning balance | $ / shares	$ 10.50
Weighted-Average Exercise Price per Share, Options granted | $ / shares	14.00
Weighted-Average Exercise Price per Share, Options exercised | $ / shares	7.89
Weighted-Average Exercise Price per Share, Options forfeited and Canceled | $ / shares	13.42
Weighted-Average Exercise Price per Share, Outstanding, Ending balance | $ / shares	11.22
Weighted-Average Exercise Price per Share, Vested and expected to vest | $ / shares	11.14
Weighted-Average Exercise Price per Share, Exercisable | $ / shares	$ 9.89
Weighted-Average Remaining Contractual Life, Outstanding	4 years 8 months 1 day
Weighted-Average Remaining Contractual Life, Vested and expected to Vest	4 years 7 months 13 days
Weighted-Average Remaining Contractual Life, Exercisable	3 years 7 months 6 days
Aggregate Intrinsic Value, Outstanding | $	$ 105,830
Aggregate Intrinsic Value, Vested and expected to Vest | $	104,749
Aggregate Intrinsic Value, Exercisable | $	$ 85,074