Summary of Significant Accounting Policies - Software Development Cost (Details) - USD ($) |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2021 |
Sep. 30, 2020 |
Sep. 30, 2021 |
Sep. 30, 2020 |
|
| Capitalized software development costs | ||||
| Intangible Assets, Net [Line Items] | ||||
| Capitalized costs | $ 1,600,000 | $ 300,000 | $ 3,900,000 | $ 700,000 |
| Amortization of capitalized software development costs | 200,000 | 0 | 200,000 | 0 |
| Capitalized software development costs | ||||
| Intangible Assets, Net [Line Items] | ||||
| Capitalized costs | 0 | 0 | 0 | 0 |
| Amortization of capitalized software development costs | $ 200,000 | $ 200,000 | $ 600,000 | $ 600,000 |