Slicers (applies to each fact value in each table cell)

Reporting Entity [Axis]

0001370637 (http://www.sec.gov/CIK)

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]	Period [Axis]
	2016-01-01 - 2016-12-31
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions	The fair value of options granted in each year using the Black-Scholes pricing model has been based on the following assumptions:   Year Ended   December 31,   2014   2015   2016 Volatility 43.0% - 49.0%   40.4% - 45.0%   38.6% - 44.6% Risk-free interest rate 1.7% - 2.1%   1.3% - 1.9%   1.1% - 2.1% Expected term (in years) 5.5 - 6.1   5.5 - 6.1   5.5 - 6.3 Dividend rate —%   —%   —%
Schedule of Share-based Compensation, Stock Options, Activity	The following table summarizes the activity for the Company’s options (in thousands except share and per share amounts):   Shares   Weighted-Average Exercise Price   Weighted-Average Remaining Contract Term (in years)   Aggregate Intrinsic Value Outstanding at December 31, 2013 13,190,420   $ 3.10         Granted 3,206,717   10.28         Exercised (4,215,628 )   1.89         Forfeited/Canceled (656,230 )   6.58         Outstanding at December 31, 2014 11,525,279   5.34         Granted 1,660,170   16.19         Exercised (1,315,735 )   2.76         Forfeited/Canceled (800,855 )   9.94         Outstanding at December 31, 2015 11,068,859   6.94         Granted 1,700,234   9.35         Exercised (2,535,620 )   4.17         Forfeited/Canceled (893,906 )   9.51         Outstanding at December 31, 2016 9,339,567   7.89   6.64   $ 43,613 Total exercisable at December 31, 2016 6,352,071   6.29   5.76   38,257 Total vested and expected to vest at December 31, 2016 9,166,097   7.82   6.60   43,364
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value	The following table summarizes the weighted average grant date fair value of options granted, intrinsic value of options exercised and fair value of awards vested in the year ended December 31, 2014, 2015 and 2016 (in thousands except per share amounts):   Year Ended December 31,   2014   2015   2016 Weighted average grant date fair value of options granted $ 4.86   $ 6.89   $ 4.03 Intrinsic value of options exercised 24,788   15,148   19,130 Fair value of awards vested 4,691   8,337   9,533
Summary of the Activity of Unvested RSUs	The following table summarizes the activity for the Company’s unvested RSUs:   Shares   Weighted-Average Fair Value Unvested at December 31, 2014 —   $ — Granted 407,368   13.78 Vested —   — Forfeited/Canceled (11,522 )   16.76 Unvested at December 31, 2015 395,846   13.70 Granted 3,200,297   10.29 Vested (255,868 )   10.64 Forfeited/Canceled (205,094 )   10.15 Unvested at December 31, 2016 3,135,181   10.70 Total vested and expected to vest at December 31, 2016 2,843,448   10.68
Schedule of Share-based Compensation, Allocation of Recognized Period Costs	Total stock-based compensation expense included in the consolidated statements of operations is as follows (in thousands):   Year Ended   December 31,   2014   2015   2016 Cost of revenue $ 1,113   $ 871   $ 1,057 Marketing 216   560   971 Product development 1,461   2,860   5,079 General and administrative 7,260   6,550   8,794 Total stock-based compensation expense $ 10,050   $ 10,841   $ 15,901