Employee Benefit Plans - Summary of Stock-Based Compensation Cost (Details) - USD ($)
$ in Thousands |
3 Months Ended |
9 Months Ended |
12 Months Ended |
Sep. 30, 2021 |
Sep. 30, 2020 |
Sep. 30, 2021 |
Sep. 30, 2020 |
Dec. 31, 2020 |
Dec. 31, 2019 |
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
|
|
|
|
|
|
| Total compensation cost recognized for stock-based compensation plans |
$ 46,803
|
$ 1,500
|
$ 132,542
|
$ 4,949
|
|
|
| Stock options |
|
|
|
|
|
|
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
|
|
|
|
|
|
| Total compensation cost recognized for stock-based compensation plans |
1,665
|
1,500
|
6,734
|
4,949
|
$ 7,100
|
$ 3,300
|
| RSUs |
|
|
|
|
|
|
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
|
|
|
|
|
|
| Total compensation cost recognized for stock-based compensation plans |
17,396
|
0
|
45,725
|
0
|
|
|
| PRSUs |
|
|
|
|
|
|
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
|
|
|
|
|
|
| Total compensation cost recognized for stock-based compensation plans |
27,675
|
0
|
80,016
|
0
|
|
|
| ESPP |
|
|
|
|
|
|
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
|
|
|
|
|
|
| Total compensation cost recognized for stock-based compensation plans |
$ 67
|
$ 0
|
$ 67
|
$ 0
|
|
|