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Hedging Activities - Derivative Instruments Fair Value (Details) - USD ($) $ in Millions | Dec. 31, 2019 | Mar. 31, 2019
--- | --- | ---
Derivatives designated for hedge accounting |  |
Derivatives, Fair Value [Line Items] |  |
Fair value of derivative, asset | $ 99 | $ 108
Fair value of derivative, liability | 53 | 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 | Cross currency swap | Prepaid expenses and other |  |
Derivatives, Fair Value [Line Items] |  |
Fair value of derivative, asset | 24 | 0
Derivatives designated for hedge accounting | Cross currency swap | Other accrued liabilities |  |
Derivatives, Fair Value [Line Items] |  |
Fair value of derivative, liability | 14 | 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 assets |  |
Derivatives, Fair Value [Line Items] |  |
Fair value of derivative, asset | 59 | 91
Derivatives designated for hedge accounting | Cross currency swap | Other noncurrent liabilities |  |
Derivatives, Fair Value [Line Items] |  |
Fair value of derivative, liability | 39 | 33
Derivatives designated for hedge accounting | Cross currency swap | Non-current Asset / Liability |  |
Derivatives, Fair Value [Line Items] |  |
U.S. Dollar notional amount, asset | 4,237 | 5,283
Derivatives not designated for hedge accounting |  |
Derivatives, Fair Value [Line Items] |  |
Fair value of derivative, asset | 3 | 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 | 3 | 0
Fair value of derivative, liability | 0 | 0
U.S. Dollar notional amount, asset | 322 | 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 | $ 14 | $ 14

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