Separate Account Liabilities Rollforward (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025	Jan. 01, 2025
Separate Account, Liability [Roll Forward]
Balance, beginning of period	$ 73,511
Separate account liabilities	71,428
Balance, end of period	71,428
Stable Value and Risk Solutions
Separate Account, Liability [Roll Forward]
Balance, beginning of period	27,605
Separate account liabilities	27,645	$ 30,290
Premiums and deposits	467	636
Policy charges	(51)	(47)
Surrenders and withdrawals	(590)	(2,288)
Benefit payments	(38)	(35)
Investment performance	(25)	525
Net transfers from (to) general account	13	1
Other	264	(1,263)
Balance, end of period	27,645	30,290
Cash Surrender Value	24,641	26,910
Stable Value and Risk Solutions \| Previously Reported
Separate Account, Liability [Roll Forward]
Balance, beginning of period		32,761
Separate account liabilities
Stable Value and Risk Solutions \| Reclassification, Segmentation Basis Change
Separate Account, Liability [Roll Forward]
Separate account liabilities			$ 0
Group annuities
Separate Account, Liability [Roll Forward]
Balance, beginning of period	18,099
Separate account liabilities	17,706	17,721
Premiums and deposits	62	56
Policy charges	(27)	(27)
Surrenders and withdrawals	(431)	(370)
Benefit payments	(11)	(10)
Investment performance	(287)	61
Net transfers from (to) general account	(7)	(16)
Other	308	100
Balance, end of period	17,706	17,721
Cash Surrender Value	6,518	6,492
Group annuities \| Previously Reported
Separate Account, Liability [Roll Forward]
Balance, beginning of period		11,001
Separate account liabilities
Group annuities \| Reclassification, Segmentation Basis Change
Separate Account, Liability [Roll Forward]
Separate account liabilities			6,926
Variable Annuity
Separate Account, Liability [Roll Forward]
Balance, beginning of period	19,554
Separate account liabilities	18,285	19,735
Premiums and deposits	14	16
Policy charges	(104)	(113)
Surrenders and withdrawals	(590)	(653)
Benefit payments	(117)	(104)
Investment performance	(467)	(227)
Net transfers from (to) general account	(4)	(24)
Other	(1)	0
Balance, end of period	18,285	19,735
Cash Surrender Value	$ 18,188	19,625
Variable Annuity \| Previously Reported
Separate Account, Liability [Roll Forward]
Balance, beginning of period		$ 27,766
Separate account liabilities
Variable Annuity \| Reclassification, Segmentation Basis Change
Separate Account, Liability [Roll Forward]
Separate account liabilities			$ (6,926)

Amount of cash outflow to separate account policyholder from benefit payment.

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- Definition

Amount of separate account liability payable to policyholder upon surrender of contract before maturity.

+ References

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Amount of increase (decrease) in separate account liability from performance of investment.

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Amount increase (decrease) in separate account liability from change, classified as other.

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Amount of decrease in separate account liability from policy charge.

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- Definition

Amount of cash inflow to separate account liability from premium and deposit from cash received.

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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.

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Amount of decrease in separate account liability from contract redemption and withdrawal of funds.

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- Definition

Amount of liability for variable contract in which all or portion of contract holder's funds is allocated to specific separate account and supported by assets held in separate account.

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Amount of transfer to (from) liability for policyholder account balance (to) from liability for separate account.

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