v3.20.4

Stockholders' Equity (Tables) | 12 Months Ended
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Dec. 31, 2020
Equity [Abstract] |
Schedule of Reserved Shares of Common Stock for Issuance | At December 31, 2020, the Company had reserved shares of common stock for issuance as follows (in thousands):
|  | As of December 31, 2020 |
Common stock awards granted under equity incentive plans |  |  | 13,088 |
Common stock awards available for issuance under the 2017 Employee Stock Purchase Plan * |  |  | 5,089 |
Common stock awards available for issuance under the 2017 Equity Incentive Plan |  |  | 21,420 |
Total reserved shares of common stock |  |  | 39,597 |
Summary of Restricted Stock Unit Activity | Restricted stock unit activity for the year ended December 31, 2020 is as follows (in thousands, except per share data):
|  | Number of Shares |  |  | Weighted Average Grant Date Fair Value Per Share |
Balance, December 31, 2019 |  |  | 4,544 |  |  | $ | 67.30 |
Awarded |  |  | 1,425 |  |  |  | 147.46 |
Released |  |  | (1,253 | ) |  |  | 66.79 |
Forfeited |  |  | (361 | ) |  |  | 76.55 |
Balance, December 31, 2020 - outstanding |  |  | 4,355 |  |  | $ | 92.91 |
Schedule of Stock Option Activity | The following table summarizes the Company’s stock option activities under the 2008 Plan and 2017 Plan (in thousands, except per share data):
|  | Number of Shares |  |  | Weighted Average Exercise Price |  |  | Weighted Average Remaining Contractual Life (Years) |  |  | Weighted Average Grant Date Fair Value Per Share |  |  | Aggregate Intrinsic Value |
Balance, December 31, 2019 |  |  | 11,124 |  |  | $ | 14.84 |  |  |  | 6.2 |  |  |  | — |  |  |  |  |
Granted |  |  | 599 |  |  |  | 145.17 |  |  |  | — |  |  | $ | 54.39 |  |  |  |  |
Exercised |  |  | (2,854 | ) |  |  | 5.89 |  |  |  | — |  |  |  | — |  |  |  |  |
Forfeited and expired |  |  | (136 | ) |  |  | 48.04 |  |  |  | — |  |  |  | — |  |  |  |  |
Balance, December 31, 2020 - outstanding |  |  | 8,733 |  |  | $ | 26.19 |  |  |  | 5.7 |  |  |  | — |  |  | $ | 2,670,743 |
Options exercisable at December 31, 2020 |  |  | 6,144 |  |  | $ | 8.00 |  |  |  | 4.8 |  |  |  | — |  |  | $ | 1,990,694 |
Schedule of Share-based Compensation Expense | The following table shows total stock-based compensation expense for the years ended December 31, 2020, 2019 and 2018 (in thousands):
|  | Years Ended December 31, |
|  | 2020 |  |  | 2019 |  |  | 2018 |
Cost of platform revenue |  | $ | 847 |  |  | $ | 342 |  |  | $ | 97 |
Cost of player revenue |  |  | 1,407 |  |  |  | 1,072 |  |  |  | 469 |
Research and development |  |  | 58,412 |  |  |  | 40,036 |  |  |  | 18,538 |
Sales and marketing |  |  | 42,846 |  |  |  | 24,179 |  |  |  | 10,459 |
General and administrative |  |  | 30,564 |  |  |  | 19,546 |  |  |  | 8,111 |
Total stock-based compensation |  | $ | 134,076 |  |  | $ | 85,175 |  |  | $ | 37,674 |
Summary of Assumptions Used to Value Stock Options Granted | The assumptions used to value stock options granted during the years ended December 31, 2020, 2019 and 2018 are as follows:
|  | Years Ended December 31, |
|  | 2020 |  |  | 2019 |  |  | 2018 |
Expected term (in years) |  | 5.0 - 6.7 |  |  | 5.0 - 6.7 |  |  | 5.3 - 6.8 |
Risk-free interest rate |  | 0.22 - 1.67% |  |  | 1.35 - 2.56% |  |  | 2.32 - 2.88% |
Expected volatility |  | 36 - 39% |  |  | 35 - 36% |  |  | 38 - 40% |
Dividend rate |  |  | — |  |  |  | — |  |  |  | — |

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