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Pension Benefits - Schedule of Other Changes in Accumulated Other Comprehensive Income (Details) - Pension Plans, Defined Benefit - USD ($) $ in Millions | 12 Months Ended
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Mar. 31, 2021 | Mar. 31, 2020 | Mar. 31, 2019
UNITED STATES |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net actuarial loss (gain) | $ 0 | $ (3) | $ 8
Amortization of: |  |  |
Net actuarial loss | 0 | (129) | (9)
Prior service credit (cost) | 0 | 0 | 0
Foreign exchange impact and other | 0 | 0 | 0
Total recognized in net periodic benefit cost and other comprehensive loss (income) | 0 | (132) | (1)
Non-U.S. Plans |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net actuarial loss (gain) | (9) | (24) | 42
Amortization of: |  |  |
Net actuarial loss | (35) | (6) | (5)
Prior service credit (cost) | 1 | 0 | 0
Foreign exchange impact and other | 15 | (6) | (12)
Total recognized in net periodic benefit cost and other comprehensive loss (income) | $ (28) | $ (36) | $ 25

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- Definition Amount, before tax, of reclassification adjustment from accumulated other comprehensive (income) loss for prior service cost (credit) of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 17A -URI http://asc.fasb.org/extlink&oid=121641772&loc=SL34724391-108580 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=121641772&loc=d3e689-108580 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=121641772&loc=d3e637-108580 + Details
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