Investments - Schedule of Loans by Property Type (Details) $ in Millions	Dec. 31, 2023 USD ($) loan	Dec. 31, 2022 USD ($) loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Cost \| $	$ 144.8	$ 159.9
Composition	100.00%	100.00%
Loan Count \| loan	28	28
Apartments
Accounts, Notes, Loans and Financing Receivable [Line Items]
Cost \| $	$ 76.1	$ 87.4
Composition	52.60%	54.50%
Loan Count \| loan	16	16
Hotel
Accounts, Notes, Loans and Financing Receivable [Line Items]
Cost \| $	$ 22.4	$ 25.0
Composition	15.40%	15.60%
Loan Count \| loan	4	4
Industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Cost \| $	$ 26.0	$ 26.0
Composition	18.00%	16.30%
Loan Count \| loan	4	4
Retail
Accounts, Notes, Loans and Financing Receivable [Line Items]
Cost \| $	$ 20.3	$ 21.5
Composition	14.00%	13.60%
Loan Count \| loan	4	4

Financing Receivable, before Allowance for Credit Loss, Number of Loans

No definition available.

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- Definition

Percentage, before allowance for credit loss, of financing receivable to total financing receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph (c)
-Publisher SEC

+ Details

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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

No definition available.

+ Details

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- Definition

Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479344/326-20-45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3B
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-3B

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-5

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Balance Type:	debit
Period Type:	instant

- Details

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Namespace Prefix:
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Balance Type:
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- Details

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Balance Type:
Period Type:

- Details

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Data Type:	na
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- Details

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