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Schedule of Accumulated Benefit Obligation in Excess of Plan Assets (Detail) - USD ($) $ in Thousands | Dec. 31, 2017 | Mar. 31, 2017
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Schedule Of Pension Plans With Accumulated And Projected Benefit Obligations In Excess Of Plan Assets [Line Items] |  |
Projected benefit obligation | $ 103,443 |
Accumulated benefit obligation | 101,287 |
Fair value of plan assets | $ 57,536 |
Predecessor |  |
Schedule Of Pension Plans With Accumulated And Projected Benefit Obligations In Excess Of Plan Assets [Line Items] |  |
Projected benefit obligation |  | $ 97,941
Accumulated benefit obligation |  | 94,467
Fair value of plan assets |  | $ 57,146

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- Definition Schedule of Pension Plans with Accumulated and Projected Benefit Obligations in Excess of Plan Assets [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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- Definition Fair value of assets that have been segregated and restricted to provide pension or postretirement benefits. Assets include, but are not limited to, stocks, bonds, other investments, earnings from investments, and contributions by the employer and employees. + 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 (b) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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