Insurance (Separate Accounts Liability) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Separate Account, Liability [Line Items]
Separate Account, Liability, Beginning Balance	$ 84,965
Separate Account, Liability, Ending Balance	87,440	$ 104,441
Variable Annuities
Separate Account, Liability [Line Items]
Separate Account, Liability, Beginning Balance	77,653	105,023
Premiums and deposits	216	432
Surrenders and withdrawals	(1,496)	(1,744)
Benefit payments	(383)	(371)
Investment performance	4,310	(6,906)
Policy charges	(519)	(580)
Net transfers from (to) separate account	(11)	(85)
Other	0	14
Separate Account, Liability, Ending Balance	79,770	95,783
Universal Life Insurance
Separate Account, Liability [Line Items]
Separate Account, Liability, Beginning Balance	5,218	6,862
Premiums and deposits	43	45
Surrenders and withdrawals	(41)	(51)
Benefit payments	(14)	(16)
Investment performance	341	(514)
Policy charges	(52)	(49)
Net transfers from (to) separate account	(12)	(15)
Other	0	0
Separate Account, Liability, Ending Balance	5,483	6,262
Company-Owned Life Insurance
Separate Account, Liability [Line Items]
Separate Account, Liability, Beginning Balance	1,932	2,384
Premiums and deposits	0	0
Surrenders and withdrawals	(3)	(7)
Benefit payments	(10)	(10)
Investment performance	111	(138)
Policy charges	(11)	(11)
Net transfers from (to) separate account	0	(2)
Other	0	(1)
Separate Account, Liability, Ending Balance	$ 2,019	$ 2,215

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

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

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

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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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