Investments - Schedule of Commercial Mortgage Loans (Details) $ in Millions	Mar. 31, 2023 USD ($) loan	Dec. 31, 2022 USD ($) loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Cost \| $	$ 159.9	$ 159.9
Composition	100.00%	100.00%
Loan Count \| loan	28	28
Apartments
Accounts, Notes, Loans and Financing Receivable [Line Items]
Cost \| $	$ 87.4	$ 87.4
Composition	54.70%	54.50%
Loan Count \| loan	16	16
Hotel
Accounts, Notes, Loans and Financing Receivable [Line Items]
Cost \| $	$ 25.0	$ 25.0
Composition	15.60%	15.60%
Loan Count \| loan	4	4
Industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Cost \| $	$ 26.0	$ 26.0
Composition	16.30%	16.30%
Loan Count \| loan	4	4
Retail
Accounts, Notes, Loans and Financing Receivable [Line Items]
Cost \| $	$ 21.5	$ 21.5
Composition	13.40%	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
-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph (c)

+ 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/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919230-210447

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=124255206&loc=SL82895884-210446

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 3B
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL120267963-210447

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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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