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Variable Interest Entities - Additional Information (Details) $ in Millions | Sep. 30, 2024 USD ($) Property | Dec. 31, 2023 Property
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Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Number of Variable Interest Entities | Property | 29 | 33
Investments in Unconsolidated Entities [Member] | Non-Consolidated VIEs [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Maximum exposure to loss, funding commitments | $ 28.7 |
Mortgage Revenue Bonds [Member] | Non-Consolidated VIEs [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Maximum exposure to loss, funding commitments | 56.4 |
Taxable Mortgage Revenue Bonds [Member] | Non-Consolidated VIEs [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Maximum exposure to loss, funding commitments | 15.4 |
Governmental Issuer Loans [Member] | Non-Consolidated VIEs [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Maximum exposure to loss, funding commitments | 19.3 |
Taxable GILs [Member] | Non-Consolidated VIEs [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Maximum exposure to loss, funding commitments | 53.4 |
Property Loans [Member] | Non-Consolidated VIEs [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Maximum exposure to loss, funding commitments | $ 0.5 |

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