SUPPLEMENTARY CONSOLIDATED FINANCIAL STATEMENT SCHEDULE VALUATION AND QUALIFYING ACCOUNTS (Details) - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Mar. 31, 2022
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Year	$ 160	$ 151	$ 261
Charges (Credits) to Costs and Expenses	819	45	29
Charged to Other Accounts	14	9	(31)
Deductions From Allowance Accounts	(62)	(45)	(108)
Balance at End of Year	931	160	151
Current allowances	921	158	144
Provision for bad debts	819	45	29
U.S. Pharmaceutical
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Provision for bad debts	725
Allowances for credit losses
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Year	114	99	211
Charges (Credits) to Costs and Expenses	819	45	29
Charged to Other Accounts	5	5	(35)
Deductions From Allowance Accounts	(61)	(35)	(106)
Balance at End of Year	877	114	99
Other allowances
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Year	46	52	50
Charges (Credits) to Costs and Expenses	0	0	0
Charged to Other Accounts	9	4	4
Deductions From Allowance Accounts	(1)	(10)	(2)
Balance at End of Year	54	46	52
Written-off
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Deductions From Allowance Accounts	(62)	(37)	(106)
Credited to other accounts and other
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Deductions From Allowance Accounts	$ 0	$ (8)	$ (2)