Income Taxes - Income Tax Related Assets And Liabilities (Details) - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Current assets:
Income tax receivables and prepaid taxes	$ 67	$ 58
Non-current:
Income taxes receivable and prepaid taxes	136	180
Deferred tax assets	289	265
Deferred tax assets, noncurrent	425	445
Deferred tax assets, total	492	503
Current liabilities:
Liability for uncertain tax positions	(30)	(12)
Income taxes payable	(368)	(75)
Deferred tax liabilities, current	(398)	(87)
Non-current:
Deferred taxes	(360)	(718)
Income taxes payable	(130)	(168)
Liability for uncertain tax positions	(364)	(271)
Deferred tax liabilities, noncurrent	(854)	(1,157)
Deferred tax liabilities, total	(1,252)	(1,244)
Income Tax Rate Reconciliation [Line Items]
Valuation allowance	3,860	$ 2,162
Net increase (decrease) in deferred tax asset valuation allowance	1,698
Net increase in deferred tax asset valuation allowance for goodwill impairment	1,565
Net decrease in deferred tax asset valuation allowance for releases	4
Net change in deferred tax asset valuation allowance for currency translation	129
Foreign
Income Tax Rate Reconciliation [Line Items]
Valuation allowance	$ 175