Insurance and Contractholder Liabilities - Unpaid Claims and Claim Expenses - Cigna Healthcare - Activity (Details) - Cigna Healthcare - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2022	Mar. 31, 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	8,024	7,755
Prior years	(276)	(233)
Total incurred	7,748	7,522
Paid costs related to:
Current year	4,634	4,640
Prior years	2,822	2,555
Total paid	7,456	7,195
Ending balance, net	4,292	3,785
Add: Reinsurance and other amounts recoverable	199	242
Ending balance	$ 4,491	$ 4,027

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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