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Commitments and Contingencies - Narrative (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Unrecorded Unconditional Purchase Obligation |  |  |
Operating leases, rent expense |  |  | $ 4.8
Operating Lease, Expense | $ 4.3 | $ 5.1 |
Assets | 19,671.9 | 17,648.7 |
Construction Contracts |  |  |
Unrecorded Unconditional Purchase Obligation |  |  |
Commitments under construction contracts | $ 2.5 |  |
Related Entity |  |  |
Unrecorded Unconditional Purchase Obligation |  |  |
Ownership percentage in partnership | 50.00% |  |
Mortgage loans originated for sale |  |  |
Unrecorded Unconditional Purchase Obligation |  |  |
Guarantor Obligations, Current Carrying Value | $ 0.4 | $ 0.6 |

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