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Income Taxes - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2021	Mar. 31, 2020
Income Tax Contingency [Line Items]
Discrete tax benefits related to statute of limitation expirations and tax settlements	$ 115
Tax expense (benefit), share-based payment arrangement	(58)	$ (10)	$ 1
European businesses held for sale	0	1,509	0
Net discrete tax benefit			105
Valuation allowance	696	726
Increase (decrease) in valuation allowance	30
Unrecognized tax benefits	1,399	1,523	1,754	$ 958
Unrecognized tax benefits that would Impact income tax expense and the effective tax rate	1,300
Income tax expense (benefit), before any tax effect, related to accrued interest and penalties	31	8	9
Accrued interest and penalties on unrecognized tax benefits	138	108
Undistributed earnings of foreign operations	4,800
Minimum
Income Tax Contingency [Line Items]
Tax liability increase due to proposed adjustment to taxable income	600
Maximum
Income Tax Contingency [Line Items]
Tax liability increase due to proposed adjustment to taxable income	700
U.K. Businesses (Disposal Group) and Austrian Business
Income Tax Contingency [Line Items]
European businesses held for sale		1,200
Held-for-sale | E.U. Businesses (Disposal Group)
Income Tax Contingency [Line Items]
European businesses held for sale		438
Federal
Income Tax Contingency [Line Items]
Federal, state and foreign net operating loss carryforwards	49
State
Income Tax Contingency [Line Items]
Federal, state and foreign net operating loss carryforwards	3,400
Foreign Tax Authority
Income Tax Contingency [Line Items]
Federal, state and foreign net operating loss carryforwards	2,000
International
Income Tax Contingency [Line Items]
European businesses held for sale			58
National Prescription Opiate Litigation
Income Tax Contingency [Line Items]
Loss contingency accrual, period increase (decrease)	(8)	274	8,100
Loss contingency accrual, period increase (decrease), net of tax		237	$ 6,800
National Prescription Opiate Litigation | Pending Litigation
Income Tax Contingency [Line Items]
Loss contingency accrual, period increase (decrease)		$ 274
Capital Loss Carryforward | Foreign Tax Authority
Income Tax Contingency [Line Items]
Federal, state and foreign net operating loss carryforwards	$ 701

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