Investments Investments (Allowance for Credit Loss Roll Forward) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Mar. 31, 2026	Dec. 31, 2025	Mar. 31, 2025	Dec. 31, 2024
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Roll Forward]
Debt Securities, Available-for-Sale, Allowance for Credit Loss	$ 246	$ 132	$ 246	$ 132	$ 232	$ 210	$ 103	$ 98
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Not Previously Recorded	33	35	97	45
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Securities Sold	(17)	0	(73)	(2)
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Not to Sell before Recovery, Credit Loss, Previously Recorded, Expense (Reversal)	(2)	(6)	12	(8)
Financing Receivable, Allowance for Credit Loss, Foreign Currency Translation	0	0	0	(1)
Allowance for Loan and Lease Losses, Real Estate	127	107	127	107	115	117	89	93
Allowance For Loan and Lease Losses Provision Of Credit Losses	12	18	17	14
Provision (release)	0	0	(7)	0
Commercial Real Estate
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Roll Forward]
Allowance for Loan and Lease Losses, Real Estate	119	103	119	103	109	112	87	93
Allowance For Loan and Lease Losses Provision Of Credit Losses	10	16	14	10
Provision (release)	0	0	(7)	0
Residential Real Estate
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Roll Forward]
Allowance for Loan and Lease Losses, Real Estate	8	4	8	4	6	5	2	0
Allowance For Loan and Lease Losses Provision Of Credit Losses	2	(2)	3	(4)
Provision (release)	0	0	0	0
Corporate Debt Securities [Member]
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Roll Forward]
Debt Securities, Available-for-Sale, Allowance for Credit Loss	224	112	224	112	211	189	88	82
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Not Previously Recorded	33	31	97	41
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Securities Sold	(17)	0	(73)	(2)
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Not to Sell before Recovery, Credit Loss, Previously Recorded, Expense (Reversal)	(3)	(7)	11	(8)
Financing Receivable, Allowance for Credit Loss, Foreign Currency Translation	0	0	0	(1)
Asset-backed Securities [Member]
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Roll Forward]
Debt Securities, Available-for-Sale, Allowance for Credit Loss	22	19	22	19	21	21	15	15
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Not Previously Recorded	0	4	0	4
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Securities Sold	0	0	0	0
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Not to Sell before Recovery, Credit Loss, Previously Recorded, Expense (Reversal)	(1)	0	(1)	0
Financing Receivable, Allowance for Credit Loss, Foreign Currency Translation	0	0	0	0
Commercial Mortgage Backed Securities [Member]
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Roll Forward]
Debt Securities, Available-for-Sale, Allowance for Credit Loss	0	1	0	1	$ 0	0	$ 0	$ 1
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Not Previously Recorded	0	0	0	0
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Securities Sold	0	0	0	0
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Not to Sell before Recovery, Credit Loss, Previously Recorded, Expense (Reversal)	0	1	0	0
Financing Receivable, Allowance for Credit Loss, Foreign Currency Translation	0	$ 0	0	$ 0
Debt Security, Government, Non-US [Member]
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Roll Forward]
Debt Securities, Available-for-Sale, Allowance for Credit Loss	$ 0		$ 0			$ 0

Allowance For Loan and Lease Losses Provision Of Credit Losses

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- Definition

Allowance For Loan And Lease Losses Writeoff Net Of Recoveries

+ References

No definition available.

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- Definition

The reserve to cover probable credit losses related to specifically identified fixed maturity real estate loans as well as probable credit losses inherent in the remainder of that loan portfolio.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
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- Definition

Amount of allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Amount of expense for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), for which no credit loss was previously recorded.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Amount of expense (reversal of expense) for allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), not intended to be sold and not more likely than not will be required to sell before recovery of amortized cost basis, with previously recorded allowance.

+ References

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-Topic 326
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- Definition

Amount of decrease in allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) from sale.

+ References

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- Definition

Amount of foreign currency translation gain (loss) which decreases (increases) allowance for credit loss on financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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