Future Policy Benefits (Rollforward of Unpaid Claims) (Details) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2023	Jun. 30, 2022
Liability for Claims and Claims Adjustment Expense [Line Items]
Balance, beginning of period	$ 16,098	$ 15,598
Less: Reinsurance recoverables	2,452	2,629
Net balance, beginning of period	13,646	12,969
Incurred related to:
Current period	13,580	13,101
Prior periods (1)	306	634
Total incurred	13,886	13,735
Paid related to:
Current period	(8,546)	(8,291)
Prior periods	(4,959)	(4,831)
Total paid	(13,505)	(13,122)
Net balance, end of period	14,027	13,582
Add: Reinsurance recoverables	2,590	2,537
Balance, end of period (included in future policy benefits and other policy-related balances)	$ 16,617	$ 16,119

The amount needed to reflect the estimated ultimate cost of settling claims relating to insured events that have occurred on or before the balance sheet date, whether or not reported to the insurer at that date.

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Amount, after effects of reinsurance, of payments to settle claims incurred in the current period and related claims settlement costs.

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Amount, after effects of reinsurance, of payments to settle claims incurred in prior periods and related claims settlement costs.

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Amount, after effects of reinsurance, of expense (reversal of expense) for claims incurred and costs incurred in the claim settlement process.

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Liability as of the balance sheet date for amounts representing estimated cost of settling unpaid claims under the terms of the underlying insurance policies, less estimated reinsurance recoveries on such claims. This includes an estimate for claims which have been incurred but not reported. Claim adjustment expenses represent the costs estimated to be incurred in the settlement of unpaid claims.

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Amount, after valuation allowance, recoverable under reinsurance contracts including premium paid under reinsurance contracts. Examples include, but are not limited to, settled and unsettled claims, incurred but not reported losses, loss adjustment expense, premium paid, policy benefits and policy reserves.

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Amount, after effects of reinsurance, of expense (reversal of expense) for claims incurred in prior reporting periods and related claims settlement costs.

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