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Stockholders' Equity - Additional Information (Detail) $ / shares in Units, $ in Thousands |  |  |  | 12 Months Ended
--- | --- | --- | --- | ---
Jun. 22, 2015 shares | Mar. 25, 2014 USD ($) $ / shares shares | Sep. 23, 2013 USD ($) $ / shares shares | Dec. 31, 2015 USD ($) Installment $ / shares shares | Dec. 31, 2014 USD ($) $ / shares shares | Dec. 31, 2013 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Preferred shares authorized |  |  |  | 5,000,000 |  |
Proceeds from public offering of common stock, net of issuance costs | $ |  |  |  |  | $ 93,796 | $ 69,492
Stock option maximum term |  |  |  | 4 years 11 months 1 day |  |
Specified stockholder ownership percentage |  |  |  | 10.00% |  |
Purchase price of common stock percent under stock incentive plans for specified stockholder |  |  |  | 110.00% |  |
Stock option maximum term for specified stockholder |  |  |  | 5 years |  |
Share of common stock subject to a stock option or stock appreciation right |  |  |  | 100.00% |  |
Fixed ratio shares of common stock |  |  |  | 1.33 |  |
Intrinsic value of options exercised | $ |  |  |  | $ 6,400 | 20,400 | 8,900
Options outstanding, Aggregate Intrinsic Value | $ |  |  |  | 14,074 |  |
Options exercisable, Aggregate Intrinsic Value | $ |  |  |  | 13,119 |  |
Options vested and expected to vest, aggregate intrinsic value | $ |  |  |  | $ 14,000 | $ 49,400 | $ 54,900
Aggregate estimated fair value of stock options vested | $ / shares |  |  |  | $ 1.4 | $ 0.5 | $ 0.5
Restricted stock units awarded |  |  |  | 446,000 |  |
Aggregate value of shares vested in period | $ |  |  |  | $ 3,500 | $ 9,100 | $ 4,100
Total payments for the employees' tax obligations to taxing authorities | $ |  |  |  | $ 1,546 | $ 4,556 | $ 2,015
Share-Based Compensation Awards, Tranche 2 [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Stock options granted vesting percentage |  |  |  | 0.33% |  |
Share-Based Compensation Awards, Tranche 3 [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Stock options granted vesting percentage |  |  |  | 0.33% |  |
2013 Stock Incentive Plan [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Percent of fair value per share of common stock on option grant date |  |  |  | 100.00% |  |
Stock options vesting period |  |  |  | 4 years |  |
Stock options expiration term |  |  |  | 10 years |  |
Stock reserved for issuance under plan |  |  |  | 14,100,000 |  |
Additional shares authorized under 2013 stock incentive plan | 5,300,000 |  |  | 4,400,000 |  |
Shares reserved for issuance of future awards |  |  |  | 4,508,405 |  |
2004 Stock Incentive Plan [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Stock reserved for issuance under plan |  |  |  | 9,700,000 |  |
2010 Employee Stock Purchase Plan [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Percent of fair value per share of common stock on option grant date |  |  |  | 85.00% |  |
Stock reserved for issuance under plan |  |  |  | 2,100,000 |  |
Purchase plan offering period |  |  |  | 2 years |  |
Purchase plan purchase period |  |  |  | 6 months |  |
Shares reserved for issuance of future awards |  |  |  | 1,292,379 |  |
Maximum [Member] | 2013 Stock Incentive Plan [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Stock option maximum term |  |  |  | 10 years |  |
Employee Stock Option [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Shares subject to repurchase rights |  |  |  | 0 |  |
Employee Stock Option [Member] | 2013 Stock Incentive Plan [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Share based vesting rights |  |  |  | Options granted under the 2013 Plan generally vest over four years at a rate of 25 percent one year from the grant date and one thirty-sixth per month thereafter and expire ten years after the grant, or earlier upon employment termination. |  |
Stock options granted vesting percentage |  |  |  | 25.00% |  |
Restricted Stock Units (RSUs) [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Share based vesting rights |  |  |  | These awards will vest as follows: one-third of the award will vest in a series of three successive equal annual installments. |  |
Restricted stock units awarded |  |  |  | 446,000 | 488,000 | 392,500
Grant date fair value of restricted stock units awarded | $ / shares |  |  |  | $ 9.45 | $ 14.05 | $ 12.12
Share-based compensation arrangement by share-based payment award, number of vesting installment | Installment |  |  |  | 3 |  |
Shares withheld from issuance in order to pay employee taxes |  |  |  | 172,807 | 309,102 | 167,138
Restricted Stock Units (RSUs) [Member] | Share-Based Compensation Awards, Tranche 1 [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Stock options granted vesting percentage |  |  |  | 0.33% |  |
Common Stock [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Public offering, common stock shares issued |  | 4,444,444 | 7,015,000 |  | 4,444,444 | 7,015,000
Public offering price of common stock issued | $ / shares |  | $ 22.50 | $ 10.58 |  |  |
Proceeds from public offering of common stock, net of issuance costs | $ |  | $ 93,800 | $ 69,500 |  |  |
Underwriters | Common Stock [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Sale of stock, number of shares issued in transaction |  |  | 915,000 |  |  |

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