MEDICARE PART D (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Segment Reporting Information [Line Items]
Other current assets	$ 6,493	$ 5,276
Trade accounts payable and accrued expenses	(4,509)	(4,013)
Other long-term assets	4,379	2,128
Other long-term liabilities	(2,383)	(1,787)
Risk Corridor Settlement
Segment Reporting Information [Line Items]
Other current assets	363	216
Trade accounts payable and accrued expenses	(68)	(39)
Net current asset	295	177
Other long-term assets	5	8
Other long-term liabilities	(194)	(90)
Net long-term liability	(189)	(82)
Total net asset	106	95
CMS Subsidies/ Discounts
Segment Reporting Information [Line Items]
Other current assets	1,894	1,420
Trade accounts payable and accrued expenses	(466)	(253)
Net current asset	1,428	1,167
Other long-term assets	0	0
Other long-term liabilities	0	0
Net long-term liability	0	0
Total net asset	$ 1,428	$ 1,167