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Variable Interest Entities - Additional Information (Details) $ in Millions	Sep. 30, 2024 USD ($) Property	Dec. 31, 2023 Property
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

X

- Definition

The number of variable interest entities owned.

+ References

No definition available.

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- Definition

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

+ References

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- 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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 20
-Name Accounting Standards Codification
-Section 40
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481628/310-20-40-7

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481990/310-10-45-2

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