Investments (Rollforward of expected credit losses Private Debt HFI) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Private Debt, Held-for-investment, Allowance for Credit Loss [Line Items]
Valuation allowance for expected credit losses - beginning of period	$ 5	$ 0	$ 4	$ 0
Provision for expected credit loss	0	0	2	0
Recovery of expected credit loss	0	0	1	0
Valuation allowance for expected credit losses - end of period	$ 5	$ 0	$ 5	$ 0

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

No definition available.

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- Definition

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

+ References

+ Details

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- Definition

Amount of increase (decrease) of allowance reserve for credit loss.

+ References

No definition available.

+ Details

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- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

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

Reference 2: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 11B
-Subparagraph (c)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-11B

Reference 3: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 310
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481696/310-30-50-2

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Accounting Standards Codification
-Section S99
-Paragraph 4
-Subparagraph (SAB Topic 6.L.1)
-SubTopic 10
-Topic 310
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480418/310-10-S99-4

+ Details

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Balance Type:	credit
Period Type:	instant