MEDICARE PART D (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Segment Reporting Information [Line Items]
Other current assets	$ 6,631	$ 5,567
Trade accounts payable and accrued expenses	(6,569)	(5,238)
Other long-term assets	3,377	3,380
Other long-term liabilities	(1,662)	(1,473)
Risk Corridor Settlement
Segment Reporting Information [Line Items]
Other current assets	224	240
Trade accounts payable and accrued expenses	(232)	(166)
Net current (liability) asset	(8)	74
Other long-term assets	17	19
Other long-term liabilities	(77)	(78)
Net long-term liability	(60)	(59)
Total net (liability) asset	(68)	15
CMS Subsidies/ Discounts
Segment Reporting Information [Line Items]
Other current assets	514	696
Trade accounts payable and accrued expenses	(1,825)	(1,236)
Net current (liability) asset	(1,311)	(540)
Other long-term assets	0	0
Other long-term liabilities	0	0
Net long-term liability	0	0
Total net (liability) asset	$ (1,311)	$ (540)