Income Taxes - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2022	Dec. 31, 2021
Income Tax Contingency [Line Items]
Effective income tax rate reconciliation, tax (benefit), share-based payment arrangement, amount			$ 55
Effective income tax rate reconciliation, GILTI, amount		$ 42		$ 81
Discrete tax benefit recognized due to statute of limitation expirations				115
Loss (gain) to remeasure disposal group to fair value			0	1,271
Unrecognized tax benefits	$ 1,500		1,500
Unrecognized tax benefits that would impact effective tax rate	1,400		1,400
Held-for-sale | E.U. Businesses (Disposal Group)
Income Tax Contingency [Line Items]
Loss (gain) to remeasure disposal group to fair value		879		1,400
Held-for-sale | U.K. and Austrian Businesses (Disposal Group)
Income Tax Contingency [Line Items]
Loss (gain) to remeasure disposal group to fair value				853
Disposed of by sale | E.U. Businesses (Disposal Group)
Income Tax Contingency [Line Items]
Loss (gain) to remeasure disposal group to fair value	(31)	$ 26	(66)	$ 517
Minimum
Income Tax Contingency [Line Items]
Possible decrease in unrecognized tax benefits during the next twelve months	170		170
Maximum
Income Tax Contingency [Line Items]
Possible decrease in unrecognized tax benefits during the next twelve months	$ 195		$ 195