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Pension Benefits - Schedule Of Weighted-Average Assumptions Used to Estimate Net Periodic Pension Expense and Actuarial Present Value of Benefit Obligations (Details) - Pension Plans, Defined Benefit | 12 Months Ended
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Mar. 31, 2018 | Mar. 31, 2017 | Mar. 31, 2016
United States |  |  |
Net periodic pension expense |  |  |
Discount rates | 3.55% | 3.40% | 3.36%
Rate of increase in compensation | 4.00% | 4.00% | 4.00%
Expected long-term rate of return on plan assets | 6.25% | 6.25% | 6.75%
Benefit obligation |  |  |
Discount rates | 3.69% | 3.39% | 3.27%
Rate of increase in compensation |  | 4.00% | 4.00%
Non-U.S. Plans |  |  |
Net periodic pension expense |  |  |
Discount rates | 2.34% | 2.72% | 2.36%
Rate of increase in compensation | 2.72% | 2.76% | 2.80%
Expected long-term rate of return on plan assets | 4.03% | 4.51% | 4.87%
Benefit obligation |  |  |
Discount rates | 2.35% | 2.35% | 2.84%
Rate of increase in compensation | 2.59% | 3.18% | 2.98%

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- Definition Weighted average rate for present value of future retirement benefits cash flows, used to determine net periodic benefit cost of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(1) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(3) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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