Hedging Activities - Derivative Instruments Fair Value (Details) - USD ($) $ in Millions	Jun. 30, 2019	Mar. 31, 2019
Derivatives designated for hedge accounting
Derivatives, Fair Value [Line Items]
Fair value of derivative, asset	$ 68	$ 108
Fair value of derivative, liability	69	51
Derivatives designated for hedge accounting \| Foreign Exchange Contract \| Prepaid expenses and other
Derivatives, Fair Value [Line Items]
Fair value of derivative, asset	16	17
Fair value of derivative, liability	0	0
U.S. Dollar notional amount, asset	81	81
Derivatives designated for hedge accounting \| Foreign Exchange Contract \| Other noncurrent assets
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	0	0
Derivatives designated for hedge accounting \| Cross Currency Swap \| Prepaid expenses and other
Derivatives, Fair Value [Line Items]
Fair value of derivative, asset	37	0
Derivatives designated for hedge accounting \| Cross Currency Swap \| Other noncurrent assets
Derivatives, Fair Value [Line Items]
Fair value of derivative, asset	15	91
Derivatives designated for hedge accounting \| Cross Currency Swap \| Other accrued liabilities
Derivatives, Fair Value [Line Items]
Fair value of derivative, liability	8	18
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	355	0
Derivatives designated for hedge accounting \| Cross Currency Swap \| Other noncurrent liabilities
Derivatives, Fair Value [Line Items]
Fair value of derivative, liability	61	33
Derivatives designated for hedge accounting \| Cross Currency Swap \| Non-current Asset / Liability
Derivatives, Fair Value [Line Items]
U.S. Dollar notional amount, asset	3,681	5,283
Derivatives not designated for hedge accounting
Derivatives, Fair Value [Line Items]
Fair value of derivative, asset	0	0
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	0	0
Fair value of derivative, liability	0	0
U.S. Dollar notional amount, asset	655	14
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	$ 3	$ 14

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
-Topic 815
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
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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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