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Pension Benefits - Narrative (Details) | 1 Months Ended | 3 Months Ended | 12 Months Ended
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Jun. 30, 2019 USD ($) participant | Mar. 31, 2022 USD ($) | Dec. 31, 2021 USD ($) | Sep. 30, 2019 USD ($) | Jun. 30, 2019 USD ($) | Mar. 31, 2022 USD ($) $ / shares | Mar. 31, 2021 USD ($) | Mar. 31, 2020 USD ($)
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |  |  |
Percentage of eligible compensation (up to percent) |  |  |  |  |  | 75.00% |  |
Contribution expenses |  |  |  |  |  | $ 116,000,000 | $ 102,000,000 | $ 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 | German Wholesale Business |  |  |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |  |  |
Pension liabilities derecognized |  |  | $ 187,000,000 |  |  |  |  |
Accumulated other comprehensive loss derecognized |  |  | $ 33,000,000 |  |  |  |  |
Held-for-sale | Austrian Business Operations |  |  |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |  |  |
Accumulated other comprehensive loss derecognized |  | $ 11,000,000 |  |  |  | $ 11,000,000 |  |
Pension Plans, Defined Benefit |  |  |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |  |  |
Unexpected actuarial losses (as a percent) (exceeding) |  | 10.00% |  |  |  | 10.00% |  |
Expected benefit payments in 2023 |  | $ 34,000,000 |  |  |  | $ 34,000,000 |  |
Expected benefit payments in 2024 |  | 33,000,000 |  |  |  | 33,000,000 |  |
Expected benefit payments in 2025 |  | 33,000,000 |  |  |  | 33,000,000 |  |
Expected benefit payments in 2026 |  | 34,000,000 |  |  |  | 34,000,000 |  |
Expected benefit payments in 2027 |  | 35,000,000 |  |  |  | 35,000,000 |  |
Expected benefit payments in 2028 through 2032 |  | 186,000,000 |  |  |  | 186,000,000 |  |
Expected contributions in next fiscal year |  | 13,000,000 |  |  |  | $ 13,000,000 |  |
Unit value of cash and cash equivalents (in dollars per share) | $ / shares |  |  |  |  |  | $ 1.00 |  |
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 |  |
Other Postretirement Benefits Plan |  |  |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |  |  |
Projected benefit obligation |  | 56,000,000 |  |  |  | 56,000,000 | 64,000,000 |
Net periodic pension expense |  |  |  |  |  | 0 | 0 | 0
U.S. Plans | Pension Plans, Defined Benefit |  |  |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |  |  |
Number of plan participants elected to receive settlement payments | participant | 1,300 |  |  |  |  |  |  |
Settlements | $ 49,000,000 |  |  |  |  | 0 | 0 |
Pre-tax pension settlement charges |  |  |  | $ 105,000,000 | $ 17,000,000 |  |  | 122,000,000
Annuity contracts purchased |  |  |  | $ 280,000,000 |  |  |  |
Accumulated other comprehensive loss |  |  |  |  |  |  |  | $ 0
Current assets |  | 0 |  |  |  | 0 | 0 |
Current liabilities |  | $ 1,000,000 |  |  |  | 1,000,000 | 1,000,000 |
Actuarial gain (loss) |  |  |  |  |  | $ 0 | $ 0 |
Discount rates |  | 3.35% |  |  |  | 3.35% | 2.35% | 3.08%
Actuarial loss |  |  |  |  |  | $ 0 | $ 0 | $ 129,000,000
Projected benefit obligation |  | $ 8,000,000 |  |  |  | $ 8,000,000 | $ 9,000,000 | $ 10,000,000
Discount rates (percent) |  | 3.35% |  |  |  | 3.35% | 2.35% | 3.08%
Increase (decrease) in basis points |  |  |  |  |  | (0.0100) |  |
Net periodic pension expense |  |  |  |  |  | $ 0 | $ 0 | $ 131,000,000
U.S. Plans | Pension Plans, Defined Benefit | German Wholesale Business |  |  |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |  |  |
Actuarial loss |  |  |  |  |  |  | 33,000,000 |
U.S. Plans | Pension Plans, Defined Benefit | Unfunded plan |  |  |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |  |  |
Projected benefit obligation |  | $ 8,000,000 |  |  |  | 8,000,000 | 9,000,000 |
Non-U.S. Plans | Pension Plans, Defined Benefit |  |  |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |  |  |
Settlements |  |  |  |  |  | 24,000,000 | 0 |
Current assets |  | 49,000,000 |  |  |  | 49,000,000 | 0 |
Current liabilities |  | $ 90,000,000 |  |  |  | 90,000,000 | 9,000,000 |
Actuarial gain (loss) |  |  |  |  |  | 55,000,000 | (89,000,000) |
Actuarial loss resulting from discount rate changes |  |  |  |  |  | $ 69,000,000 | $ (32,000,000) |
Discount rates |  | 2.67% |  |  |  | 2.67% | 1.89% | 2.03%
Actuarial gain (loss), demographic and assumption changes |  |  |  |  |  | $ (14,000,000) | $ (57,000,000) |
Actuarial loss |  |  |  |  |  | 14,000,000 | 35,000,000 | $ 6,000,000
Projected benefit obligation |  | $ 701,000,000 |  |  |  | $ 701,000,000 | $ 875,000,000 | $ 896,000,000
Discount rates (percent) |  | 2.67% |  |  |  | 2.67% | 1.89% | 2.03%
Increase (decrease) in basis points |  |  |  |  |  | (0.0078) |  |
Amounts of plan exceeding total plan contribution |  |  |  |  |  | $ 20,000,000 | $ 22,000,000 | $ 17,000,000
Percentage of total plan contribution - exceeding (percent) |  |  |  |  |  | 5.00% |  |
Funded status (as a percent) |  | 88.00% |  |  |  | 88.00% |  |
Amounts accrued for liability |  | $ 0 |  |  |  | $ 0 |  |
Net periodic pension expense |  |  |  |  |  | 4,000,000 | 19,000,000 | 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 |  |  |  | 35,000,000 | 36,000,000 |
Non-U.S. Plans | Pension Plans, Defined Benefit | Unfunded plan |  |  |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |  |  |
Projected benefit obligation |  | $ 101,000,000 |  |  |  | $ 101,000,000 | $ 162,000,000 |
Termination of U.S Defined Benefit Pension Plan and Settlement of Retirement Benefits | U.S. Plans | Pension Plans, Defined Benefit |  |  |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |  |  |
Actuarial loss |  |  |  |  |  |  |  | $ 127,000,000

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- Definition Amount of cost for defined contribution plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 70 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942 + Details
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- Definition Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan. + References No definition available. + Details
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- Definition Amount of the obligation recognized by withdrawing from a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers. + References No definition available. + Details
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- Definition Amount of liability, recognized in statement of financial position, for defined benefit pension and other postretirement plans, classified as current. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=123453770&loc=d3e1731-114919 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=123450688&loc=d3e4179-114921 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(20)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=123453770&loc=d3e1703-114919 + Details
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