MEDICARE PART D (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Segment Reporting Information [Line Items]
Other current assets	$ 6,136	$ 5,567
Trade accounts payable and accrued expenses	(7,600)	(5,238)
Other long-term assets	3,638	3,380
Other long-term liabilities	(1,595)	(1,473)
Risk Corridor Settlement
Segment Reporting Information [Line Items]
Other current assets	131	240
Trade accounts payable and accrued expenses	(150)	(166)
Net current (liability) asset	(19)	74
Other long-term assets	235	19
Other long-term liabilities	(123)	(78)
Net long-term asset (liability)	112	(59)
Total net asset (liability)	93	15
CMS Subsidies/ Discounts
Segment Reporting Information [Line Items]
Other current assets	517	696
Trade accounts payable and accrued expenses	(3,566)	(1,236)
Net current (liability) asset	(3,049)	(540)
Other long-term assets	0	0
Other long-term liabilities	0	0
Net long-term asset (liability)	0	0
Total net asset (liability)	$ (3,049)	$ (540)