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Pension Benefits - Narrative (Details) | 3 Months Ended | 12 Months Ended |
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Dec. 31, 2022 USD ($) | Jun. 30, 2022 USD ($) | Mar. 31, 2022 USD ($) | Dec. 31, 2020 USD ($) | Mar. 31, 2023 USD ($) $ / shares | Mar. 31, 2022 USD ($) | Mar. 31, 2021 USD ($) | Oct. 31, 2022 USD ($)
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |  |  |
Percentage of eligible compensation (up to percent) |  |  |  |  | 75.00% |  |  |
Contribution expenses |  |  |  |  | $ 125,000,000 | $ 116,000,000 | $ 102,000,000 |
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% |  |  |
Held-for-sale | E.U. Businesses (Disposal Group) |  |  |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |  |  |
Pension assets |  |  | $ 3,024,000,000 |  |  | 3,024,000,000 |  |
Held-for-sale | U.K. Businesses (Disposal Group) |  |  |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |  |  |
Pension assets |  |  | 1,482,000,000 |  |  | 1,482,000,000 |  |
Held-for-sale | Austrian Business Operations |  |  |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |  |  |
Accumulated other comprehensive gain (loss) derecognized |  |  | (11,000,000) |  | $ (17,000,000) | (11,000,000) |  |
Held-for-sale | German Wholesale Business |  |  |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |  |  |
Accumulated other comprehensive gain (loss) derecognized |  |  |  | $ (33,000,000) |  |  |  |
Pension liabilities derecognized |  |  |  | $ 187,000,000 |  |  |  |
Disposal Group, Disposed of by Sale, Not Discontinued Operations | E.U. Businesses (Disposal Group) |  |  |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |  |  |
Pension assets |  |  |  |  |  |  |  | $ 1,300,000,000
Disposal group, including discontinued operations, pension plan obligation derecognized | $ 75,000,000 |  |  |  |  |  |  |
Accumulated other comprehensive gain (loss) derecognized | $ 13,000,000 |  |  |  |  |  |  |
Disposal Group, Disposed of by Sale, Not Discontinued Operations | U.K. Businesses (Disposal Group) |  |  |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |  |  |
Accumulated other comprehensive gain (loss) derecognized |  | $ 30,000,000 |  |  |  |  |  |
Pension Plans, Defined Benefit |  |  |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |  |  |
Unexpected actuarial losses (as a percent) (exceeding) |  |  |  |  | 10.00% |  |  |
Expected benefit payments in 2024 |  |  |  |  | $ 8,000,000 |  |  |
Expected benefit payments in 2025 |  |  |  |  | 9,000,000 |  |  |
Expected benefit payments in 2026 |  |  |  |  | 9,000,000 |  |  |
Expected benefit payments in 2027 |  |  |  |  | 9,000,000 |  |  |
Expected benefit payments in 2028 |  |  |  |  | 9,000,000 |  |  |
Expected benefit payments in 2029 through 2033 |  |  |  |  | 50,000,000 |  |  |
Expected contributions in next fiscal year |  |  |  |  | $ 3,000,000 |  |  |
Unit value of cash and cash equivalents (in dollars per share) | $ / shares |  |  |  |  | $ 1.00 |  |  |
Pension Plans, Defined Benefit | Held-for-sale | E.U. Businesses (Disposal Group) |  |  |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |  |  |
Pension liabilities |  |  | 85,000,000 |  |  | 85,000,000 |  |
Pension Plans, Defined Benefit | Held-for-sale | U.K. Businesses (Disposal Group) |  |  |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |  |  |
Pension assets |  |  | 49,000,000 |  |  | 49,000,000 |  |
Pension Plans, Defined Benefit | Held-for-sale | Austrian Business Operations |  |  |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |  |  |
Pension liabilities derecognized |  |  | 43,000,000 |  |  | 43,000,000 |  |
Pension Plans, Defined Benefit | Disposal Group, Disposed of by Sale, Not Discontinued Operations | U.K. Businesses (Disposal Group) |  |  |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |  |  |
Disposal group, including discontinued operations, pension plan assets derecognized |  | $ 49,000,000 |  |  |  |  |  |
Other Postretirement Benefits Plan |  |  |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |  |  |
Projected benefit obligation |  |  | $ 56,000,000 |  | $ 45,000,000 | 56,000,000 |  |
Net periodic pension expense |  |  |  |  | 0 | 0 | 0 |
UNITED STATES | Pension Plans, Defined Benefit | German Wholesale Business |  |  |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |  |  |
Actuarial loss |  |  |  |  |  |  | $ 33,000,000 |
Non-U.S. Plans | Pension Plans, Defined Benefit |  |  |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |  |  |
Actuarial gain (loss) |  |  |  |  | 65,000,000 | 55,000,000 |  |
Actuarial loss resulting from discount rate changes |  |  |  |  | $ 69,000,000 | $ 69,000,000 |  |
Discount rates (percent) |  |  | 2.67% |  | 4.54% | 2.67% | 1.89% |
Actuarial gain (loss), demographic and assumption changes |  |  |  |  | $ (4,000,000) | $ (14,000,000) |  |
Actuarial loss |  |  |  |  | 9,000,000 | 14,000,000 | $ 35,000,000 |
Projected benefit obligation |  |  | $ 701,000,000 |  | $ 172,000,000 | 701,000,000 | 875,000,000 |
Increase (decrease) in basis points |  |  |  |  | 0.0187 |  |  |
Percentage of total plan contribution - exceeding (percent) |  |  |  |  | 5.00% |  |  |
Amounts of plan exceeding total plan contribution |  |  |  |  | $ 19,000,000 | 20,000,000 | 22,000,000 |
Funded status (as a percent) |  |  |  |  | 85.00% |  |  |
Amounts accrued for liability |  |  |  |  | $ 0 |  |  |
Net periodic pension expense |  |  |  |  | 7,000,000 | 4,000,000 | $ 19,000,000 |
Non-U.S. Plans | Pension Plans, Defined Benefit | Norwegian Public Service Pension Fund (SPK) |  |  |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |  |  |
Amount of plan asset value |  |  | 35,000,000 |  | 30,000,000 | 35,000,000 |  |
Non-U.S. Plans | Pension Plans, Defined Benefit | Unfunded plan |  |  |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |  |  |
Projected benefit obligation |  |  | $ 101,000,000 |  | $ 18,000,000 | $ 101,000,000 |  |

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