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Pension Benefits - Narrative (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Mar. 31, 2026 | Mar. 31, 2025 | Mar. 31, 2024
Defined Benefit Plan Disclosure [Line Items] |  |  |
Percentage of eligible compensation (up to percent) | 75.00% |  |
Contribution expenses | $ 141 | $ 128 | $ 138
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 |  |
Defined benefit plan, plan assets, foreign currency translation gain (loss) | 34 |  |
Other Postretirement Benefits Plan |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net periodic pension expense | 0 | 0 | 0
Defined benefit plan, benefit obligation | 42 | 40 |
Non-U.S. Plans | UK Pension Plan |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Non-cash pre-tax settlement charge | (87) |  |
Non-U.S. Plans | Pension Plans, Defined Benefit |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net periodic pension expense | 3 | 60 | $ 5
Defined benefit plan, benefit obligation | 40 | 77 |
Defined benefit plan assets | 25 | 66 |
Defined benefit plan, funded status | (15) | (11) |
Accumulated benefit obligations | $ 39 | $ 74 |

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