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Schedule of Carrying Value of Trust Assets, Including Unrealized Gains or Losses (Detail) - USD ($) $ in Thousands | Dec. 31, 2017 | Mar. 31, 2017
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Defined Benefit Plan Disclosure [Line Items] |  |
Investments held in Rabbi Trust at fair value | $ 8,908 |
Obligations under the supplemental plan | $ 32,508 |
Predecessor |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Investments held in Rabbi Trust at fair value |  | $ 8,759
Obligations under the supplemental plan |  | $ 29,108

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- Definition Carrying amount as of the balance sheet date of assets held under deferred compensation agreements. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.17) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Details
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