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Commitments and Contingencies - Additional Information (Details) - USD ($) $ in Millions |  | 12 Months Ended |
--- | --- | --- | ---
Jun. 10, 2016 | Dec. 31, 2020 | Dec. 31, 2019 | Sep. 30, 2021
Loss Contingencies [Line Items] |  |  |  |
Community development related to claim |  |  |  | $ 220.2
Board of Directors Chairman | Performance Shares |  |  |  |
Loss Contingencies [Line Items] |  |  |  |
Shares granted vested and accelerated |  | 34,276 | 34,276 |
OCD vs ICF Emergency |  |  |  |
Loss Contingencies [Line Items] |  |  |  |
Loss contingency damages sought value | $ 200.8 |  |  |
Road Home Contract |  |  |  |
Loss Contingencies [Line Items] |  |  |  |
Contract term, period | 3 years |  |  |
Contract award, value | $ 912.0 |  |  |

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