Hedging Activities - Derivative Instruments Fair Value (Details) - USD ($) $ in Millions	Sep. 30, 2021	Mar. 31, 2021
Derivatives designated for hedge accounting
Derivatives, Fair Value [Line Items]
Fair value of derivative, asset	$ 67	$ 76
Fair value of derivative, liability	110	146
Derivatives designated for hedge accounting \| Cross currency swap \| Prepaid expenses and other
Derivatives, Fair Value [Line Items]
Fair value of derivative, asset	2	4
Derivatives designated for hedge accounting \| Cross currency swap \| Other accrued liabilities
Derivatives, Fair Value [Line Items]
Fair value of derivative, liability	36	47
Derivatives designated for hedge accounting \| Cross currency swap \| Prepaid expenses and other/Other accrued liabilities
Derivatives, Fair Value [Line Items]
U.S. Dollar notional amount, asset	838	826
Derivatives designated for hedge accounting \| Cross currency swap \| Other noncurrent assets
Derivatives, Fair Value [Line Items]
Fair value of derivative, asset	62	72
Derivatives designated for hedge accounting \| Cross currency swap \| Other noncurrent liabilities
Derivatives, Fair Value [Line Items]
Fair value of derivative, liability	74	92
Derivatives designated for hedge accounting \| Cross currency swap \| Non-current Asset / Liability
Derivatives, Fair Value [Line Items]
U.S. Dollar notional amount, asset	2,474	2,663
Derivatives designated for hedge accounting \| Forward starting interest rate swaps \| Other accrued liabilities
Derivatives, Fair Value [Line Items]
Fair value of derivative, asset	0	0
Fair value of derivative, liability	0	7
U.S. Dollar notional amount, asset	0	704
Derivatives designated for hedge accounting \| Forward starting interest rate swaps \| Other noncurrent liabilities
Derivatives, Fair Value [Line Items]
Fair value of derivative, asset	3	0
Fair value of derivative, liability	0	0
U.S. Dollar notional amount, asset	200	0
Derivatives not designated for hedge accounting
Derivatives, Fair Value [Line Items]
Fair value of derivative, asset	0	0
Fair value of derivative, liability	0	1
Derivatives not designated for hedge accounting \| Foreign Exchange Contract \| Prepaid expenses and other
Derivatives, Fair Value [Line Items]
Fair value of derivative, asset	0	0
Fair value of derivative, liability	0	0
U.S. Dollar notional amount, asset	1	29
Derivatives not designated for hedge accounting \| Foreign Exchange Contract \| Other accrued liabilities
Derivatives, Fair Value [Line Items]
Fair value of derivative, asset	0	0
Fair value of derivative, liability	0	1
U.S. Dollar, notional amount, liability	$ 18	$ 10

Nominal or face amount used to calculate payments on the derivative asset.

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Nominal or face amount used to calculate payments on the derivative liability.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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