Hedging Activities - Derivative Instruments Fair Value (Details) - USD ($) $ in Millions	Jun. 30, 2020	Mar. 31, 2020
Derivatives designated for hedge accounting
Derivatives, Fair Value [Line Items]
Fair value of derivative, asset	$ 143	$ 294
Fair value of derivative, liability	26	19
Derivatives designated for hedge accounting \| Cross currency swap \| Prepaid expenses and other
Derivatives, Fair Value [Line Items]
Fair value of derivative, asset	40	112
Derivatives designated for hedge accounting \| Cross currency swap \| Other accrued liabilities
Derivatives, Fair Value [Line Items]
Fair value of derivative, liability	8	19
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	925	1,279
Derivatives designated for hedge accounting \| Cross currency swap \| Other noncurrent assets
Derivatives, Fair Value [Line Items]
Fair value of derivative, asset	103	182
Derivatives designated for hedge accounting \| Cross currency swap \| Other noncurrent liabilities
Derivatives, Fair Value [Line Items]
Fair value of derivative, liability	7	0
Derivatives designated for hedge accounting \| Cross currency swap \| Non-current Asset / Liability
Derivatives, Fair Value [Line Items]
U.S. Dollar notional amount, asset	3,313	3,313
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	3	0
U.S. Dollar notional amount, asset	500	0
Derivatives designated for hedge accounting \| Forward starting interest rate swaps \| Other noncurrent liabilities
Derivatives, Fair Value [Line Items]
Fair value of derivative, asset	0	0
Fair value of derivative, liability	8	0
U.S. Dollar notional amount, asset	674	0
Derivatives not designated for hedge accounting
Derivatives, Fair Value [Line Items]
Fair value of derivative, asset	1	2
Fair value of derivative, liability	0	0
Derivatives not designated for hedge accounting \| Foreign Exchange Contract \| Prepaid expenses and other
Derivatives, Fair Value [Line Items]
Fair value of derivative, asset	1	2
Fair value of derivative, liability	0	0
U.S. Dollar notional amount, asset	27	24
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	0
U.S. Dollar, notional amount, liability	$ 5	$ 5

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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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

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