GOODWILL AND OTHER INTANGIBLE ASSETS - Goodwill by Segments (Details) $ in Millions	6 Months Ended
	Jun. 30, 2022 USD ($)
Goodwill
Goodwill, beginning balance	$ 11,092
Acquisitions	150
Goodwill, ending balance	8,911
Disposal Group, Held-for-sale, Not Discontinued Operations
Goodwill
Goodwill, ending balance	2,331
Retail
Goodwill
Goodwill, beginning balance	1,933
Acquisitions	10
Goodwill, ending balance	1,943
Retail | Disposal Group, Held-for-sale, Not Discontinued Operations
Goodwill
Goodwill, ending balance	0
Group and Specialty
Goodwill
Goodwill, beginning balance	261
Acquisitions	0
Goodwill, ending balance	261
Group and Specialty | Disposal Group, Held-for-sale, Not Discontinued Operations
Goodwill
Goodwill, ending balance	0
Healthcare Services
Goodwill
Goodwill, beginning balance	8,898
Acquisitions	140
Goodwill, ending balance	6,707
Healthcare Services | Disposal Group, Held-for-sale, Not Discontinued Operations
Goodwill
Goodwill, ending balance	$ 2,331