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Variable Interest Entities - Additional Information (Details) $ in Millions	Sep. 30, 2023 USD ($) Property	Dec. 31, 2022 Property
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Variable Interest Entities | Property	31	35
Investments in Unconsolidated Entities [Member] | Non-Consolidated VIEs [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Maximum exposure to loss, funding commitments	$ 28.5
Mortgage Revenue Bonds [Member] | Non-Consolidated VIEs [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Maximum exposure to loss, funding commitments	99.8
Taxable Mortgage Revenue Bonds [Member] | Non-Consolidated VIEs [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Maximum exposure to loss, funding commitments	19.4
Governmental Issuer Loans [Member] | Non-Consolidated VIEs [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Maximum exposure to loss, funding commitments	56.6
Taxable Governmental Issuer Loans [Member] | Non-Consolidated VIEs [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Maximum exposure to loss, funding commitments	53.6
Property Loans [Member] | Non-Consolidated VIEs [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Maximum exposure to loss, funding commitments	$ 31.7

X

- Definition

The number of variable interest entities owned.

+ References

No definition available.

+ Details

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X

- Definition

Variable interest entity, maximum loss exposure, funding commitments, amount.

+ References

No definition available.

+ Details

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X

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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