GOODWILL AND INTANGIBLE ASSETS - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2022	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Intangible Assets [Line Items]
Decrease in goodwill		$ 0	$ 18
Accumulated goodwill impairment losses		0
Aggregate amortization expense related to finite-lived intangible assets		$ 2,300	$ 1,800	$ 1,700
Discount rate of acquired IPR&D		7.50%	7.50%	6.50%
In-process research and development impairments		$ 50	$ 2,700	$ 0
In Process Research And Development Trodelvy For HR+/HER2-
Intangible Assets [Line Items]
Indefinite-lived intangible assets, fair value	$ 6,100	$ 6,100
In Process Research And Development Trodelvy For HR+/HER2- | Fair Value, Nonrecurring
Intangible Assets [Line Items]
In-process research and development impairments	2,700		2,700
MYR
Intangible Assets [Line Items]
Decrease in goodwill	$ 18		$ 18
Immunomedics, Inc. | In Process Research And Development Trodelvy For HR+/HER2-
Intangible Assets [Line Items]
Aggregate fair value of acquired IPR&D					$ 8,800
Immunomedics, Inc. | In Process Research And Development Trodelvy For HR+/HER2- | Measurement Input, Discount Rate
Intangible Assets [Line Items]
Discount rate, measurement input	6.75%