Medical Costs Payable (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2024	Sep. 30, 2023
Causes of Increase (Decrease) in Liability for Unpaid Claims and Claims Adjustment Expense [Line Items]
Medical costs payable, beginning of period	$ 32,395	$ 29,056
Acquisitions (dispositions), net	(755)	1
Reported medical costs:
Current year	197,750	180,423
Prior year	(600)	(760)
Total reported medical costs	197,150	179,663
Medical payments:
Payments for current year	(165,544)	(149,671)
Payments for prior years	(29,095)	(26,257)
Total medical payments	(194,639)	(175,928)
Less: medical costs payable included within businesses held for sale	(200)	0
Medical costs payable, end of period	$ 33,951	$ 32,792

Liability For Claims And Claims Adjustment Expense Attributable To Disposal Groups

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

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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- Definition

Amount of increase (decrease) in the cost of settling unpaid claims after deduction of reinsurance recoveries related to the acquisition of a business. Includes, but is not limited to, claims which have been incurred but not reported.

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

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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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