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Pension Benefits - Summary of Pension Plan Assets Using Fair Value Hierarchy by Asset Class (Details) - USD ($) $ in Millions | Mar. 31, 2023 | Mar. 31, 2022 | Mar. 31, 2021
--- | --- | --- | ---
Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | $ 110 | $ 175 | $ 4
Pension Plans, Defined Benefit | Non-U.S. Plans |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 174 | 681 | $ 735
Pension Plans, Defined Benefit | Non-U.S. Plans | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 144 | 641 |
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 | 7 | 382 |
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 | 27 | 84 |
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 | 110 | 175 |
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 | 7 | 15 |
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 | 7 | 15 |
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 | 18 | 38 |
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 | 0 |
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 | 18 | 38 |
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 | 0 | 6 |
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 | 0 |
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 | 0 | 6 |
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 | 0 | 11 |
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 | 0 |
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 | 0 | 11 |
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 | 7 | 361 |
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 | 0 | 336 |
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 | 7 | 25 |
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 | 0 |
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 | 110 | 173 |
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 | 110 | 173 |
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 | 2 | 37 |
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 | 30 | 40 |
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 | 0 | 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 | 2 | 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 | $ 0 | $ 2 |

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