Investments (Rollforward of expected credit losses Private Debt HFI) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2023	Dec. 31, 2022
Private Debt, Held-for-investment, Allowance for Credit Loss [Line Items]
Private debt held-to-maturity, amortized cost	$ 5	$ 0	$ 5	$ 0	$ 5	$ 4	$ 0	$ 0
Allowance for Loan and Lease Losses, Period Increase (Decrease)	1	0	2	0
Allowance for Loan and Lease Loss, Recovery of Bad Debts	(1)	0	(1)	0
Debt Securities, Available for sale, Allowance for Credit Loss	$ 122	$ 193	$ 122	$ 193	$ 115	$ 156	$ 168	$ 169

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

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- Definition

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

+ References

No definition available.

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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 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

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