Income Taxes - Components Of Deferred Tax Balances (Details) - USD ($) $ in Millions	Mar. 31, 2022	Mar. 31, 2021
Assets
Receivable allowances	$ 49	$ 69
Opioid-related litigation and claims	755	724
Compensation and benefit related accruals	285	305
Net operating loss and credit carryforwards	739	974
Lease obligations	422	539
Other	83	115
Subtotal	2,333	2,726
Less: valuation allowance	(726)	(864)
Total assets	1,607	1,862
Liabilities
Inventory valuation and other assets	(1,993)	(1,939)
Fixed assets and systems development costs	(184)	(196)
Intangibles	(233)	(411)
Lease right-of-use assets	(401)	(505)
Other	(17)	(37)
Total liabilities	(2,828)	(3,088)
Net deferred tax liability	1,221	1,226
Long-term deferred tax asset	197	185
Long-term deferred tax liability	(1,418)	$ (1,411)
Held-for-sale \| European Businesses (Disposal Group)
Liabilities
Net deferred tax liability	$ 48

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