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Retirement Plans (Schedule of Assumptions Used) (detail) | 12 Months Ended
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Mar. 31, 2017 | Mar. 31, 2016
Schedule of Assumbptions Used [Abstract] |  |
Discount rate - benefit obligation | 4.35% | 4.36%
Expected return on plan assets | 7.25% | 7.25%
Rate of compensation increase | 3.00% | 3.00%
Defined Benefit Plan Weighted Average Assumptions Used In Calculating Net Periodic Benefit Cost [Abstract] |  |
Discount rate - pension expense | 4.34% | 4.15%
Discount rate - service cost | 4.67% | 4.15%
Discount rate - interest cost | 3.62% | 4.15%
Expected return on plan assets | 7.25% | 7.25%
Rate of compensation increase | 3.00% | 3.00%

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- Definition The interest rate used to adjust for the time value of money relating to service cost. + References No definition available. + Details
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- Definition The interest rate used to adjust for the time value of money for the 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=65897934&loc=d3e1928-114920 + Details
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- Definition Expected rate of compensation increases (for pay-related plans). + 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)(2) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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- Definition Expected rate of compensation increases (for pay-related plans). + 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)(2) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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