The amount of change in fair value of funds withheld embedded derivative.

No definition available.

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- Definition

Amount of embedded derivative asset.

+ References

No definition available.

+ 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

Net other asset (liability) held in support of reserves associated with funds withheld agreements.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of the reinsurer's funds held on its behalf by the ceding insurer, including funds held in trust, under reinsurance treaties or contracts with the assuming insurer as security for the payment of the obligations thereunder.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(10))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of funds held as security for payments to be received under reinsurance contracts.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 944
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479838/944-20-50-3

+ 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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Reinsurance - Funds Withheld (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025	Dec. 31, 2025
Funds Held under Reinsurance Agreements, Asset [Line Items]
Net assets	$ 16,561.6		$ 16,561.6		$ 17,908.9
Funds withheld payable	16,386.2		16,386.2		17,783.4
Embedded derivative asset	3,524.6		3,524.6		2,633.4
Change in fair value of funds withheld embedded derivative	818.2	$ (265.9)	891.2	$ (455.3)
Fixed maturities, available-for-sale
Funds Held under Reinsurance Agreements, Asset [Line Items]
Net assets	12,083.3		12,083.3		13,300.1
Fixed maturities, trading
Funds Held under Reinsurance Agreements, Asset [Line Items]
Net assets	190.7		190.7		279.3
Equity securities
Funds Held under Reinsurance Agreements, Asset [Line Items]
Net assets	0.3		0.3		0.3
Mortgage loans
Funds Held under Reinsurance Agreements, Asset [Line Items]
Net assets	1,562.6		1,562.6		2,002.9
Other investments
Funds Held under Reinsurance Agreements, Asset [Line Items]
Net assets	1,931.2		1,931.2		1,708.7
Cash and cash equivalents
Funds Held under Reinsurance Agreements, Asset [Line Items]
Net assets	747.7		747.7		547.8
Accrued interest income
Funds Held under Reinsurance Agreements, Asset [Line Items]
Net assets	149.2		149.2		159.0
Net other assets (liabilities)
Funds Held under Reinsurance Agreements, Asset [Line Items]
Net asset (liability)	$ (103.4)		$ (103.4)		$ (89.2)