|
Stock-based Compensation Plans and Awards (Tables)
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12 Months Ended |
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Dec. 31, 2014
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| Disclosure of Compensation Related Costs, Share-based Payments [Abstract] |
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| Schedule of shares available for grant and activity |
Shares available for grant as of December 31, 2014 and the activity during the twelve months ended December 31, 2014 are as follows:
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Shares Available for Grant |
|
Equity Awards |
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ESPP |
|
Total |
Balance as of December 31, 2013 |
9,048,200 |
|
|
— |
|
|
9,048,200 |
|
Additional shares authorized |
7,815,837 |
|
|
4,000,000 |
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|
11,815,837 |
|
Options granted |
(349,500 |
) |
|
— |
|
|
(349,500 |
) |
Restricted stock granted |
(4,909,360 |
) |
|
— |
|
|
(4,909,360 |
) |
ESPP shares issued |
— |
|
|
(142,265 |
) |
|
(142,265 |
) |
Options forfeited |
1,639,935 |
|
|
— |
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|
1,639,935 |
|
Restricted stock forfeited |
1,081,348 |
|
|
— |
|
|
1,081,348 |
|
Balance as of December 31, 2014 |
14,326,460 |
|
|
3,857,735 |
|
|
18,184,195 |
|
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| Schedule of assumptions used for determining the per-share fair value of shares granted under the ESPP |
The per-share fair value of shares to be granted under the ESPP is determined on the first day of the offering period using the Black-Scholes option pricing model using the following assumptions:
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Twelve months ended
December 31, |
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2014 |
Expected life (in years) |
0.5 |
|
Risk-free interest rate |
0.06 |
% |
Expected volatility |
42 |
% |
Expected dividend yield |
0 |
% |
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| Schedule of stock option activity |
Stock option activity during the twelve months ended December 31, 2014 was as follows:
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Options Outstanding |
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Outstanding
Stock Options |
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Weighted-Average Exercise Price |
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Weighted-Average Remaining Contractual Term (in years) |
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Aggregate Intrinsic Value (1) |
|
(in thousands, except share and per share data) |
Balance as of December 31, 2013 |
22,708,200 |
|
|
$ |
4.85 |
|
|
5.76 |
|
$ |
493,866 |
|
Granted |
349,500 |
|
|
35.61 |
|
|
|
|
|
Exercised |
(10,437,509 |
) |
|
1.62 |
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|
|
|
Forfeited |
(1,639,935 |
) |
|
11.49 |
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|
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Balance as of December 31, 2014 |
10,980,256 |
|
|
7.91 |
|
|
1.08 |
|
120,033 |
|
Exercisable as of December 31, 2014 |
7,958,775 |
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|
4.39 |
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|
0.40 |
|
108,296 |
|
Expected to vest as of December 31, 2014 (2) |
2,719,853 |
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|
$ |
17.05 |
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|
2.82 |
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$ |
10,822 |
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(1)Amounts represent the difference between the exercise price and the fair value of common stock at each period end for all in the money options outstanding based on the fair value per share of common stock of $26.60 and $17.83 as of December 31, 2013 and 2014. |
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(2)Options expected to vest reflect an estimated forfeiture rate. |
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| Schedule of assumptions used for estimating the per-share fair value of stock options |
The per-share fair value of stock options granted during the twelve months ended January 31, 2013, the eleven months ended December 31, 2013 and the twelve months ended December 31, 2014 was determined on the grant date using the Black-Scholes option pricing model with the following assumptions:
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Twelve months ended
January 31, |
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Eleven months ended
December 31, |
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Twelve months ended
December 31, |
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2013 |
|
2013 |
|
2014 |
Expected life (in years) |
6.02 - 6.67 |
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|
5.99 - 6.32 |
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|
6.08 |
|
Risk-free interest rate |
0.99% - 1.52% |
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|
1.00% - 2.04% |
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|
1.71% - 1.93% |
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Expected volatility |
56% - 57% |
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|
58% - 59% |
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|
58% - 59% |
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Expected dividend yield |
0 |
% |
|
0 |
% |
|
0 |
% |
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| Schedule of activities for RSUs |
The following table summarizes the activities for our RSUs for the twelve months ended December 31, 2014:
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Number of RSUs |
|
Weighted-Average Grant Date Fair Value |
Unvested as of December 31, 2013 |
10,365,512 |
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|
$ |
14.31 |
|
Granted |
4,909,360 |
|
|
32.29 |
|
Vested |
(3,169,456 |
) |
|
13.85 |
|
Forfeited |
(1,081,348 |
) |
|
19.06 |
|
Unvested as of December 31, 2014 |
11,024,068 |
|
|
21.99 |
|
Expected to vest as of December 31, 2014 (1) |
9,914,453 |
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|
$ |
21.88 |
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(1) RSUs expected to vest reflect an estimated forfeiture rate. |
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| Schedule of stock-based compensation expenses related to all employee and non-employee stock-based awards |
Stock-based compensation expense related to all employee and non-employee stock-based awards was as follows:
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Twelve months ended
January 31, |
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Eleven months ended
December 31, |
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Twelve months ended
December 31, |
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2013 |
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2013 |
|
2014 |
|
(in thousands) |
Stock-based compensation expense |
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Cost of revenue—Other
|
$ |
1,214 |
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$ |
1,946 |
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|
$ |
4,414 |
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Product development |
4,530 |
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|
8,802 |
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|
17,546 |
|
Sales and marketing |
12,294 |
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|
20,222 |
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|
42,165 |
|
General and administrative |
7,462 |
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|
9,071 |
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|
22,930 |
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Total stock-based compensation expense |
$ |
25,500 |
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|
$ |
40,041 |
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|
$ |
87,055 |
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