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v3.22.2.2

Stockholders' Equity - RSUs and Revest Shares (Details) |  | 3 Months Ended | 9 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | ---
Jan. 31, 2022 USD ($) | Sep. 30, 2022 USD ($) | Sep. 30, 2021 USD ($) | Sep. 30, 2022 USD ($) | Sep. 30, 2021 USD ($) | Dec. 31, 2020 cofounder shares | Dec. 31, 2021 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Stock-based compensation expense |  | $ 39,378,000 | $ 36,636,000 | $ 114,378,000 | $ 100,900,000 |  |
Signal Sciences Corp. |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Number of cofounders with shares subject to revesting | cofounder |  |  |  |  |  | 3 |
Shares held back for restricted stock awards, revesting period |  |  |  |  |  | 2 years |
Signal Sciences Corp. | Common Stock—Class A |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Number of shares restricted for stock awards (in shares) | shares |  |  |  |  |  | 896,499 |
RSUs |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Award vesting period |  |  |  | 4 years |  |  |
Stock-based compensation expense |  | 27,800,000 | 23,000,000 | $ 72,900,000 | 52,000,000 |  |
Modification expense |  | 1,900,000 | 3,900,000 | $ 1,900,000 | 3,900,000 |  |
RSUs | First Year |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Award vesting period |  |  |  | 4 years |  |  |
Award vesting percentage |  |  |  | 25.00% |  |  |
RSUs | Remaining Period |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Award vesting period |  |  |  | 36 months |  |  |
Revest Shares |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Stock-based compensation expense |  | 7,300,000 | $ 11,000,000 | $ 27,600,000 | $ 32,900,000 |  |
Nonvested shares sold that remain unvested (in shares) | shares |  |  |  |  |  |  | 224,124
Proceeds from nonvested shares sold | $ 10,700,000 |  |  |  |  |  |
Modification expense, incremental fair value |  | $ 0 |  | $ 5,600,000 |  |  |

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