Insurance and Contractholder Liabilities - Unpaid Claims and Claim Expenses - Cigna Healthcare - Activity (Details) - Cigna Healthcare - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021
Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward]
Beginning balance	$ 4,261	$ 3,695
Less: Reinsurance and other amounts recoverable	261	237
Beginning balance, net	4,000	3,458
Incurred costs related to:
Current year	15,751	15,716
Prior years	(268)	(228)
Total incurred	15,483	15,488
Paid costs related to:
Current year	11,900	12,065
Prior years	3,290	2,858
Total paid	15,190	14,923
Ending balance, net	4,293	4,023
Add: Reinsurance and other amounts recoverable	197	205
Ending balance	$ 4,490	$ 4,228

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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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, after effects of reinsurance, of payments to settle insured claims and pay costs incurred in the claims settlement process.

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Amount, after valuation allowance, recoverable under reinsurance contracts for losses reported to the ceding insurer but not yet paid and amounts expected for incurred losses and settlement expenses, which have not yet been reported to the ceding insurer.

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Amount, after effects of reinsurance, of expense for claims incurred in the current reporting period and related claims settlement costs.

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