Investments (Rollforward of expected credit losses Private Debt HFI) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Private Debt, Held-for-investment, Allowance for Credit Loss [Line Items]
Private Debt Held-for-investment, Allowance for Credit Loss, Beginning Balance	$ 4	$ 4
Private Debt Held-for-investment, Allowance for Credit Loss, Period Increase (Decrease)	0	1
Private Debt Held-for-investment, Allowance for Credit Loss, Recovery	1	0
Private Debt Held-for-investment, Allowance for Credit Loss, Ending Balance	$ 3	$ 5

Private Debt, Held-for-investment, Allowance for Credit Loss

No definition available.

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479344/326-20-45-1

+ Details

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

- Definition

Amount of increase (decrease) in allowance for credit loss on financing receivable.

+ References

+ Details

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Period Type:	duration

- Definition

Amount of increase in allowance for credit loss on financing receivable from recovery.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 11B
-Subparagraph (c)(4)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-11B

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 79
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479294/326-20-55-79

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

+ Details

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Balance Type:	credit
Period Type:	duration