Investments - Schedule of Commercial Mortgage Loans (Details) $ in Millions	Sep. 30, 2024 USD ($) loan	Dec. 31, 2023 USD ($) loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at cost \| $	$ 234.9	$ 144.8
Composition	100.00%	100.00%
Loan Count \| loan	17	28
Residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at cost \| $	$ 11.6
Composition	4.90%
Loan Count \| loan	1
Apartments
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at cost \| $	$ 69.5	$ 76.1
Composition	29.60%	52.60%
Loan Count \| loan	9	16
Hotel
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at cost \| $	$ 12.5	$ 22.4
Composition	5.30%	15.40%
Loan Count \| loan	1	4
Industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at cost \| $	$ 95.6	$ 26.0
Composition	40.70%	18.00%
Loan Count \| loan	3	4
Office
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at cost \| $	$ 26.0
Composition	11.10%
Loan Count \| loan	1
Retail
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at cost \| $	$ 19.7	$ 20.3
Composition	8.40%	14.00%
Loan Count \| loan	2	4

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

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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

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

+ 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
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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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