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Pension Benefits - Narrative (Details) $ in Millions | 12 Months Ended
--- | ---
Mar. 31, 2025 USD ($) | Mar. 31, 2024 USD ($) | Mar. 31, 2023 USD ($)
Defined Benefit Plan Disclosure [Line Items] |  |  |
Percentage of eligible compensation (up to percent) | 75.00% |  |
Contribution expenses | $ 128 | $ 138 | $ 125
First Part Of Pay Contribution |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Company match employee contributions (as a percent) | 100.00% |  |
Employee contributions (as a percent) | 3.00% |  |
Second Part Of Pay Contribution |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Company match employee contributions (as a percent) | 50.00% |  |
Employee contributions (as a percent) | 2.00% |  |
UK Pension Plan |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Pension losses | $ 53 |  |
Foreign exchange impact and other | 34 |  |
Defined benefit plan assets | 7 |  |
UK Pension Plan | Non-U.S. Plans |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Pre-tax settlement gain (loss) | $ (87) |  |
Pension Plans, Defined Benefit |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Unexpected actuarial losses (as a percent) (exceeding) | 10.00% |  |
Expected contributions in next fiscal year | $ 3 |  |
Pension Plans, Defined Benefit | Non-U.S. Plans |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Foreign exchange impact and other | 1 | 2 |
Defined benefit plan assets | 66 | 171 | $ 174
Actuarial gain (loss) | $ (2) | $ 0 |
Discount rates | 4.48% | 4.55% | 4.54%
Rate of increase in compensation | 3.47% | 3.21% | 3.21%
Accumulated benefit obligations | $ 74 | $ 172 |
Accumulated other comprehensive loss | 12 | 58 |
Defined benefit plan, benefit obligation | $ 77 | 174 | $ 172
Increase (decrease) in basis points | 0.0007 |  |
Net periodic pension expense | $ 60 | 5 | 7
Pension Plans, Defined Benefit | Non-U.S. Plans | Norwegian Public Service Pension Fund (SPK) |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Amount of plan asset value | 34 | 30 |
Pension Plans, Defined Benefit | Non-U.S. Plans | Unfunded plan |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, benefit obligation | 19 | 19 |
Other Postretirement Benefits Plan |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, benefit obligation | 40 | 42 |
Net periodic pension expense | 0 | $ 0 | 0
Disposed of by Sale | E.U. Businesses (Disposal Group) |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Disposal group, including discontinued operations, pension plan obligation derecognized |  |  | 75
Disposal group, including discontinued operations, pension plan assets derecognized |  |  | 49
Accumulated other comprehensive gain (loss) derecognized |  |  | 17
Held-for-sale | E.U. And U.K. Businesses (Disposal Group) |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Accumulated other comprehensive gain (loss) derecognized |  |  | $ (17)
Held-for-sale | U.K. Businesses (Disposal Group) |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Accumulated other comprehensive gain (loss) derecognized | $ (53) |  |

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