Investments Investments (Allowance for Credit Loss Roll Forward) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025	Jun. 30, 2026	Dec. 31, 2025	Jun. 30, 2025	Dec. 31, 2024
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Roll Forward]
Debt Securities, Available-for-Sale, Allowance for Credit Loss	$ 216	$ 161	$ 216	$ 161	$ 246	$ 210	$ 132	$ 98
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Not Previously Recorded	30	25	127	70
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Securities Sold	(41)	(2)	(114)	(4)
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Not to Sell before Recovery, Credit Loss, Previously Recorded, Expense (Reversal)	(13)	5	(1)	(3)
Financing Receivable, Allowance for Credit Loss, Foreign Currency Translation	0	1	0	0
Allowance for Loan and Lease Losses, Real Estate	142	113	142	113	127	117	107	93
Allowance For Loan and Lease Losses Provision Of Credit Losses	15	6	32	20
Provision (release)	0	0	(7)	0
Debt Securities, Available-for-Sale, Transfer in, Allowance for Credit Loss, Expense	(6)	0	(6)	0
Commercial Real Estate
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Roll Forward]
Allowance for Loan and Lease Losses, Real Estate	133	108	133	108	119	112	103	93
Allowance For Loan and Lease Losses Provision Of Credit Losses	14	5	28	15
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	9	5	9	5	8	5	4	0
Allowance For Loan and Lease Losses Provision Of Credit Losses	1	(1)	4	(5)
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	195	141	195	141	224	189	112	82
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Not Previously Recorded	30	25	127	66
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Securities Sold	(41)	(2)	(114)	(4)
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Not to Sell before Recovery, Credit Loss, Previously Recorded, Expense (Reversal)	(12)	5	(1)	(3)
Financing Receivable, Allowance for Credit Loss, Foreign Currency Translation	0	1	0	0
Debt Securities, Available-for-Sale, Transfer in, Allowance for Credit Loss, Expense	(6)	0	(6)	0
Asset-backed Securities [Member]
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Roll Forward]
Debt Securities, Available-for-Sale, Allowance for Credit Loss	21	19	21	19	22	21	19	15
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Not Previously Recorded	0	0	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	0	0
Financing Receivable, Allowance for Credit Loss, Foreign Currency Translation	0	0	0	0
Debt Securities, Available-for-Sale, Transfer in, Allowance for Credit Loss, Expense	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	$ 1	$ 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	0	0	0
Financing Receivable, Allowance for Credit Loss, Foreign Currency Translation	0	0	0	0
Debt Securities, Available-for-Sale, Transfer in, Allowance for Credit Loss, Expense	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
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-Subparagraph (SX 210.7-03(a)(1)(c))
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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

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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

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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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- 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 credit loss expense on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) transferred into available-for-sale out of investment in debt security measured at amortized cost (held-to-maturity).

+ 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

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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

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