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Pension Benefits - Summary of Pension Plan Assets Using Fair Value Hierarchy by Asset Class (Details) - USD ($) $ in Millions | Mar. 31, 2022 | Mar. 31, 2021 | Mar. 31, 2020
--- | --- | --- | ---
Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | $ 175 | $ 4 |
Pension Plans, Defined Benefit | Non-U.S. Plans |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 681 | 735 | $ 594
Pension Plans, Defined Benefit | Non-U.S. Plans | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 641 | 683 |
Pension Plans, Defined Benefit | Non-U.S. Plans | Level 1 | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 382 | 162 |
Pension Plans, Defined Benefit | Non-U.S. Plans | Level 2 | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 84 | 517 |
Pension Plans, Defined Benefit | Non-U.S. Plans | Level 3 | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 175 | 4 |
Pension Plans, Defined Benefit | Non-U.S. Plans | Cash and cash equivalents | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 15 | 5 |
Pension Plans, Defined Benefit | Non-U.S. Plans | Cash and cash equivalents | Level 1 | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 15 | 5 |
Pension Plans, Defined Benefit | Non-U.S. Plans | Cash and cash equivalents | Level 2 | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Pension Plans, Defined Benefit | Non-U.S. Plans | Cash and cash equivalents | Level 3 | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Pension Plans, Defined Benefit | Non-U.S. Plans | Equity commingled funds | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 38 | 181 |
Pension Plans, Defined Benefit | Non-U.S. Plans | Equity commingled funds | Level 1 | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 64 |
Pension Plans, Defined Benefit | Non-U.S. Plans | Equity commingled funds | Level 2 | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 38 | 117 |
Pension Plans, Defined Benefit | Non-U.S. Plans | Equity commingled funds | Level 3 | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Pension Plans, Defined Benefit | Non-U.S. Plans | Government securities | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 6 | 149 |
Pension Plans, Defined Benefit | Non-U.S. Plans | Government securities | Level 1 | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 5 |
Pension Plans, Defined Benefit | Non-U.S. Plans | Government securities | Level 2 | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 6 | 144 |
Pension Plans, Defined Benefit | Non-U.S. Plans | Government securities | Level 3 | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Pension Plans, Defined Benefit | Non-U.S. Plans | Corporate bonds | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 11 | 36 |
Pension Plans, Defined Benefit | Non-U.S. Plans | Corporate bonds | Level 1 | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 6 |
Pension Plans, Defined Benefit | Non-U.S. Plans | Corporate bonds | Level 2 | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 11 | 30 |
Pension Plans, Defined Benefit | Non-U.S. Plans | Corporate bonds | Level 3 | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Pension Plans, Defined Benefit | Non-U.S. Plans | Fixed income commingled funds | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 361 | 274 |
Pension Plans, Defined Benefit | Non-U.S. Plans | Fixed income commingled funds | Level 1 | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 336 | 51 |
Pension Plans, Defined Benefit | Non-U.S. Plans | Fixed income commingled funds | Level 2 | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 25 | 222 |
Pension Plans, Defined Benefit | Non-U.S. Plans | Fixed income commingled funds | Level 3 | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 1 |
Pension Plans, Defined Benefit | Non-U.S. Plans | Annuity contracts | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 173 | 0 |
Pension Plans, Defined Benefit | Non-U.S. Plans | Annuity contracts | Level 1 | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Pension Plans, Defined Benefit | Non-U.S. Plans | Annuity contracts | Level 2 | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Pension Plans, Defined Benefit | Non-U.S. Plans | Annuity contracts | Level 3 | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 173 | 0 |
Pension Plans, Defined Benefit | Non-U.S. Plans | Real estate funds and Other | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 37 | 38 |
Pension Plans, Defined Benefit | Non-U.S. Plans | Real estate funds and Other | Assets held at NAV practical expedient |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 40 | 52 |
Pension Plans, Defined Benefit | Non-U.S. Plans | Real estate funds and Other | Level 1 | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 31 | 31 |
Pension Plans, Defined Benefit | Non-U.S. Plans | Real estate funds and Other | Level 2 | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 4 | 4 |
Pension Plans, Defined Benefit | Non-U.S. Plans | Real estate funds and Other | Level 3 | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | $ 2 | $ 3 |

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