v3.19.3.a.u2

Stock-Based Compensation - Narrative (Details) $ / shares in Units, $ in Thousands |  |  | 12 Months Ended |
--- | --- | --- | --- | ---
Dec. 05, 2018 USD ($) shares | Nov. 30, 2018 shares | Dec. 31, 2019 USD ($) installment $ / shares shares | Dec. 31, 2018 USD ($) | Dec. 31, 2017 USD ($) | Aug. 31, 2016 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Aggregate number of shares authorized for issuance (in shares) |  |  | 64,900,000.0 |  |  |
Total intrinsic value of options exercised (less than for the year ended December 31, 2017) | $ |  |  | $ 75,600 | $ 5,300 | $ 100 |
Consideration for options exercised | $ |  |  | $ 47,200 |  |  |
Options issued (in shares) |  |  | 7,354,268 |  |  |
Strike price (usd per share) | $ / shares |  |  | $ 19.58 |  |  |
Weighted average grant date fair value of such options (usd per share) | $ / shares |  |  | $ 11.35 |  |  |
Compensation costs | $ |  |  | $ 81,122 | 72,565 | 40,055 |
Total unrecognized compensation cost related to non-vested stock-based compensation | $ |  |  | $ 194,800 |  |  |
Weighted-average period of cost expected to be recognized |  |  | 3 years 1 month |  |  |
Service-based awards |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Vesting period |  |  | 4 years |  |  |
Service-based awards | Twelve months of continued employment or service |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Vesting period |  |  | 12 months |  |  |
Vesting percentage |  |  | 25.00% |  |  |
Service-based awards | Following twelve quarters |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Vesting period |  |  | 36 months |  |  |
Number of installments | installment |  |  | 12 |  |  |
Stock options |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Aggregate number of shares authorized for issuance (in shares) |  |  | 46,800,000.0 |  |  |
Compensation costs | $ |  |  | $ 74,780 | 63,288 | 31,724 |
Employee stock purchase plan |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Compensation costs | $ |  |  | 1,217 | 0 | 0 |
Restricted common stock |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Aggregate fair value of restricted stock awards vested | $ |  |  | $ 2,300 | 11,900 | 21,100 |
Stock issued (in shares) |  |  | 0 |  |  |
Weighted average grant date fair value of such restricted stock (usd per share) | $ / shares |  |  | $ 0.00 |  |  |
Performance-based awards |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Compensation costs | $ |  |  | $ 9,800 | $ 10,600 | $ 800 |
2018 Equity Plan |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Aggregate number of shares authorized for issuance (in shares) |  | 13,000,000 |  |  |  |
Annual percentage increase of shares reserved and available for issuance |  | 4.00% |  |  |  |
Shares available for future grant (in shares) |  |  | 18,100,000 |  |  |
2016 Equity Plan | Stock options |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Expiration period |  |  | 10 years |  |  |
2013 Option Plan |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Shares available for future grant (in shares) |  |  |  |  |  | 0
ESPP | Employee stock purchase plan |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Aggregate number of shares authorized for issuance (in shares) | 810,000 |  |  |  |  |
Shares available for future grant (in shares) |  |  | 600,000 |  |  |
Offering period | 6 months |  |  |  |  |
Purchase period | 6 months |  |  |  |  |
Purchase price at which shares are sold, percent | 85.00% |  |  |  |  |
Minimum percentage of compensation through payroll deductions | 1.00% |  |  |  |  |
Maximum percentage of compensation through payroll deductions | 50.00% |  |  |  |  |
Maximum shares to be purchased during purchase period (in shares) | 3,000 |  |  |  |  |
Maximum value of shares to be purchased during purchase period | $ | $ 25,000 |  |  |  |  |
Purchase of common stock under employee stock purchase plan (in shares) |  |  | 171,343 |  |  |
Weighted average fair value per share (usd per share) | $ / shares |  |  | $ 16.87 |  |  |

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