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Schedule of Projected and Accumulated Benefit Obligation (Detail) - USD ($) $ in Thousands | Dec. 31, 2017 | Mar. 31, 2017
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Schedule Of Defined Benefit Plan Change In Benefit Obligation [Line Items] |  |
Projected benefit obligation | $ 103,443 |
Accumulated benefit obligation | $ 101,287 |
Predecessor |  |
Schedule Of Defined Benefit Plan Change In Benefit Obligation [Line Items] |  |
Projected benefit obligation |  | $ 97,941
Accumulated benefit obligation |  | $ 94,467

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- Definition Schedule of Defined Benefit Plan Change in Benefit Obligation [Line Items] + References No definition available. + Details
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- Definition Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level. + 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 (e) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Amount of actuarial present value of benefits attributed to service rendered by employee for 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 (a) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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