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Stockholders' Equity - Restricted Stock Units (Revest shares), Narrative (Details) |  | 12 Months Ended
--- | --- | ---
Jan. 31, 2022 USD ($) | Dec. 31, 2023 USD ($) $ / shares | Dec. 31, 2022 USD ($) $ / shares | Dec. 31, 2021 USD ($) $ / shares shares | Dec. 31, 2020 cofounder shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Stock-based compensation expense |  | $ 136,303,000 | $ 145,796,000 | $ 140,488,000 |
Signal Sciences Corp |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Number of shares restricted for stock awards (in shares) | shares |  |  |  |  | 896,499
Number of cofounders with shares subject to revesting | cofounder |  |  |  |  | 3
Shares held back for restricted stock awards, revesting period |  |  |  |  | 2 years
RSUs |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Granted (in dollars per share) | $ / shares |  | $ 15.80 | $ 14.63 | $ 54.92 |
Vested in period, grant date fair value |  | $ 127,300,000 | $ 97,900,000 | $ 67,700,000 |
Stock-based compensation expense |  | 105,200,000 | 98,500,000 | $ 78,300,000 |
Unrecognized stock-based compensation cost |  | $ 177,100,000 |  |  |
Weighted-average period of recognition |  | 2 years 4 months 24 days |  |  |
RSUs | Minimum |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Award vesting period |  | 3 years |  |  |
RSUs | Maximum |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Award vesting period |  | 4 years |  |  |
RSUs | First Year | Minimum |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Award vesting period |  | 3 years |  |  |
Award vesting percentage per year |  | 25.00% |  |  |
RSUs | First Year | Maximum |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Award vesting period |  | 4 years |  |  |
Award vesting percentage per year |  | 33.00% |  |  |
RSUs | Remaining Period | Minimum |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Award vesting period |  | 24 months |  |  |
RSUs | Remaining Period | Maximum |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Award vesting period |  | 36 months |  |  |
RSAs |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Stock-based compensation expense |  | $ 0 | 27,600,000 |  |
Unrecognized stock-based compensation cost |  | 0 |  |  |
Nonvested shares sold that remain unvested (in shares) | shares |  |  |  | 224,124 |
Proceeds from nonvested shares sold | $ 10,700,000 |  |  |  |
Incremental cost due to plan modification |  | $ 0 | $ 5,600,000 |  |

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