Investments - Allowance for Credit Losses (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Investments, Debt and Equity Securities [Abstract]
Accrued interest receivables on available-for-sale fixed maturity securities	$ 477	$ 451	$ 477	$ 451	$ 470
Debt Securities, Available-for-Sale, Allowance for Credit Loss [Roll Forward]
Beginning balance	75	47	69	45
Securities for which credit losses were not previously recorded		3	3	3
Available-for-sale securities accounted for as PCD assets	1		1
Securities disposed during the period (realized)	16	6	16	6
Additional increases to the allowance for credit losses on securities that had an allowance recorded in a previous period	3	7	6	9
Ending balance	63	51	63	51
Corporate bonds and other
Debt Securities, Available-for-Sale, Allowance for Credit Loss [Roll Forward]
Beginning balance	31	15	28	13
Securities for which credit losses were not previously recorded		3	3	3
Available-for-sale securities accounted for as PCD assets	1		1
Securities disposed during the period (realized)	16	6	16	6
Additional increases to the allowance for credit losses on securities that had an allowance recorded in a previous period		2		4
Ending balance	16	14	16	14
Asset-backed
Debt Securities, Available-for-Sale, Allowance for Credit Loss [Roll Forward]
Beginning balance	44	32	41	32
Securities for which credit losses were not previously recorded
Available-for-sale securities accounted for as PCD assets
Securities disposed during the period (realized)
Additional increases to the allowance for credit losses on securities that had an allowance recorded in a previous period	3	5	6	5
Ending balance	$ 47	$ 37	$ 47	$ 37

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2A

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479130/326-30-45-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 3A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479106/326-30-50-3A

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 3B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479106/326-30-50-3B

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

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Amount excluding accrued interest, 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
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479130/326-30-45-1

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- Definition

Amount, excluding accrued interest, 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) with no credit loss previously recorded.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479106/326-30-50-9

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
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Amount, excluding accrued interest, of credit loss expense (reversal of expense) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) with previously recorded allowance and not intended to be sold and not more likely than not will be required to sell before recovery of amortized cost basis.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479106/326-30-50-9

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
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-Publisher FASB
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Amount, excluding accrued interest, 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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479106/326-30-50-9

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- Definition

Amount, excluding accrued interest, of allowance for credit loss at acquisition date of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) purchased with credit deterioration.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 10
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479106/326-30-50-10

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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- References

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