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Pension Benefits - Summary of Pension Plan Assets Using Fair Value Hierarchy by Asset Class (Details) - USD ($) $ in Millions | Mar. 31, 2025 | Mar. 31, 2024 | Mar. 31, 2023
--- | --- | --- | ---
Pension Plans, Defined Benefit | Non-U.S. Plans |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan assets | $ 66 | $ 171 | $ 174
Pension Plans, Defined Benefit | Non-U.S. Plans | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan assets | 32 | 141 |
Pension Plans, Defined Benefit | Non-U.S. Plans | Cash and cash equivalents | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan assets | 7 | 7 |
Pension Plans, Defined Benefit | Non-U.S. Plans | Equity commingled funds | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan assets | 12 | 20 |
Pension Plans, Defined Benefit | Non-U.S. Plans | Government securities | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan assets | 6 | 4 |
Pension Plans, Defined Benefit | Non-U.S. Plans | Corporate bonds | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan assets | 4 | 4 |
Pension Plans, Defined Benefit | Non-U.S. Plans | Annuity contracts | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan assets | 0 | 103 |
Pension Plans, Defined Benefit | Non-U.S. Plans | Real estate funds and other | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan assets | 3 | 3 |
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] |  |  |
Defined benefit plan assets | 34 | 30 |
Level 1 | Pension Plans, Defined Benefit | Non-U.S. Plans | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan assets | 8 | 7 |
Level 1 | Pension Plans, Defined Benefit | Non-U.S. Plans | Cash and cash equivalents | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan assets | 7 | 7 |
Level 1 | Pension Plans, Defined Benefit | Non-U.S. Plans | Equity commingled funds | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan assets | 0 | 0 |
Level 1 | Pension Plans, Defined Benefit | Non-U.S. Plans | Government securities | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan assets | 1 | 0 |
Level 1 | Pension Plans, Defined Benefit | Non-U.S. Plans | Corporate bonds | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan assets | 0 | 0 |
Level 1 | Pension Plans, Defined Benefit | Non-U.S. Plans | Annuity contracts | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan assets | 0 | 0 |
Level 1 | Pension Plans, Defined Benefit | Non-U.S. Plans | Real estate funds and other | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan assets | 0 | 0 |
Level 2 | Pension Plans, Defined Benefit | Non-U.S. Plans | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan assets | 24 | 31 |
Level 2 | Pension Plans, Defined Benefit | Non-U.S. Plans | Cash and cash equivalents | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan assets | 0 | 0 |
Level 2 | Pension Plans, Defined Benefit | Non-U.S. Plans | Equity commingled funds | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan assets | 12 | 20 |
Level 2 | Pension Plans, Defined Benefit | Non-U.S. Plans | Government securities | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan assets | 5 | 4 |
Level 2 | Pension Plans, Defined Benefit | Non-U.S. Plans | Corporate bonds | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan assets | 4 | 4 |
Level 2 | Pension Plans, Defined Benefit | Non-U.S. Plans | Annuity contracts | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan assets | 0 | 0 |
Level 2 | Pension Plans, Defined Benefit | Non-U.S. Plans | Real estate funds and other | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan assets | 3 | 3 |
Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan assets | 0 | 103 | $ 110
Level 3 | Pension Plans, Defined Benefit | Non-U.S. Plans | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan assets | 0 | 103 |
Level 3 | Pension Plans, Defined Benefit | Non-U.S. Plans | Cash and cash equivalents | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan assets | 0 | 0 |
Level 3 | Pension Plans, Defined Benefit | Non-U.S. Plans | Equity commingled funds | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan assets | 0 | 0 |
Level 3 | Pension Plans, Defined Benefit | Non-U.S. Plans | Government securities | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan assets | 0 | 0 |
Level 3 | Pension Plans, Defined Benefit | Non-U.S. Plans | Corporate bonds | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan assets | 0 | 0 |
Level 3 | Pension Plans, Defined Benefit | Non-U.S. Plans | Annuity contracts | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan assets | 0 | 103 |
Level 3 | Pension Plans, Defined Benefit | Non-U.S. Plans | Real estate funds and other | Investment Assets at Fair Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan assets | $ 0 | $ 0 |

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