v3.19.3

Redeemable Convertible Preferred Stock, Common Stock, and Equity (Deficit) (Tables) | 9 Months Ended
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Sep. 30, 2019
Equity [Abstract] |
Summary of Activity in Restricted Common Stock | The following table summarizes the activity related to the Company’s restricted common stock for the nine months ended September 30, 2019 (in thousands, except per share amounts):
|  | Number of Shares |  | Weighted-average Grant-Date Fair Value per Share
Unvested restricted common stock as of December 31, 2018 |  | 898 |  |  | $ | 34.81 |
Vested |  | (485 | ) |  | $ | 34.84 |
Canceled and forfeited |  | (61 | ) |  | $ | 34.57 |
Unvested restricted common stock as of September 30, 2019 |  | 352 |  |  | $ | 34.77 |
Summary of Stock Options and SAR Activity | A summary of stock option and SAR activity for the nine months ended September 30, 2019 is as follows (in millions, except share amounts which are reflected in thousands, per share amounts, and years):
|  | SARs Outstanding Number of SARs |  | Options Outstanding Number of Shares |  | Weighted-Average Exercise Price Per Share |  | Weighted-Average Remaining Contractual Life (in years) |  | Aggregate Intrinsic Value
As of December 31, 2018 |  | 758 |  |  | 42,936 |  |  | $ | 9.22 |  |  | 5.74 |  | $ | 1,456 |
Granted |  | 86 |  |  | 250 |  |  | $ | 43.00 |  |  |  |  |
Exercised |  | — |  |  | (1,272 | ) |  | $ | 2.55 |  |  |  |  |
Canceled and forfeited |  | (13 | ) |  | (1,382 | ) |  | $ | 33.19 |  |  |  |  |
As of September 30, 2019 |  | 831 |  |  | 40,532 |  |  | $ | 8.89 |  |  | 4.89 |  | $ | 934 |
Vested and expected to vest as of September 30, 2019 |  | 648 |  |  | 35,145 |  |  | $ | 4.58 |  |  | 4.63 |  | $ | 933 |
Exercisable as of September 30, 2019 |  | 648 |  |  | 35,145 |  |  | $ | 4.58 |  |  | 4.63 |  | $ | 933 |
Schedule of Restricted Stock Units Activity | The following table summarizes the activity related to the Company’s RSUs for the nine months ended September 30, 2019. For purposes of this table, vested RSUs represent the shares for which the service condition had been fulfilled during nine months ended September 30, 2019 (in thousands, except per share amounts):
|  | Number of Shares |  | Weighted-Average Grant-Date Fair Value per Share
Unvested and outstanding as of December 31, 2018 |  | 75,835 |  |  | $ | 37.20 |
Granted |  | 52,859 |  |  | $ | 43.67 |
Vested |  | (27,255 | ) |  | $ | 37.38 |
Canceled and forfeited |  | (10,440 | ) |  | $ | 40.40 |
Unvested and outstanding as of September 30, 2019 |  | 90,999 |  |  | $ | 42.47 |
Schedule of Stock-Based Compensation Expense by Function | The following table summarizes total stock-based compensation expense by function for the three and nine months ended September 30, 2018 and 2019 (in millions):
|  | Three Months Ended September 30, |  | Nine Months Ended September 30,
|  | 2018 |  | 2019 |  | 2018 |  | 2019
Operations and support |  | $ | 4 |  |  | $ | 26 |  |  | $ | 11 |  |  | $ | 431 |
Sales and marketing |  | 2 |  |  | 16 |  |  | 6 |  |  | 229 |
Research and development |  | 49 |  |  | 262 |  |  | 60 |  |  | 2,822 |
General and administrative |  | 9 |  |  | 97 |  |  | 70 |  |  | 871 |
Total |  | $ | 64 |  |  | $ | 401 |  |  | $ | 147 |  |  | $ | 4,353 |

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- Definition Tabular disclosure of the number and weighted-average grant date fair value for restricted stock units that were outstanding at the beginning and end of the year, and the number of restricted stock units that were granted, vested, or forfeited during the year. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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- Definition Tabular disclosure of the number and weighted-average exercise prices (or conversion ratios) for stock options and stock appreciation rights that were outstanding at the beginning and end of the year, exercisable at the end of the year, and the number of stock options and stock appreciation rights that were granted, exercised or converted, forfeited, and expired during the year. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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