Medical Costs Payable (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2024	Mar. 31, 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	(687)	1
Reported medical costs:
Current year	66,045	60,315
Prior year	(310)	(470)
Total reported medical costs	65,735	59,845
Medical payments:
Payments for current year	(38,652)	(35,087)
Payments for prior years	(24,759)	(22,006)
Total medical payments	(63,411)	(57,093)
Medical costs payable, end of period	$ 34,032	$ 31,809

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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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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