Income Taxes - Components Of Deferred Tax Balances (Details) - USD ($) $ in Millions	Mar. 31, 2025	Mar. 31, 2024
Assets
Receivable allowances	$ 136	$ 244
Opioid-related litigation and claims	680	680
Compensation and benefit-related accruals	287	277
Net operating loss and credit carryforwards	847	751
Lease obligations	423	438
Capitalized research and development cost	68	60
Intangibles	66	5
Other	170	147
Subtotal	2,677	2,602
Less: valuation allowance	(644)	(653)
Total assets	2,033	1,949
Liabilities
Inventory valuation and other assets	(2,139)	(2,092)
Fixed assets	(72)	(16)
Lease right-of-use assets	(434)	(431)
Other	(50)	(10)
Total liabilities	(2,695)	(2,549)
Net deferred tax liability	(662)	(600)
Long-term deferred tax asset	367	317
Long-term deferred tax liability	$ (1,029)	$ (917)

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