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Summary of Deferred Stock Unit Activity (Detail) - Predecessor - $ / shares | 4 Months Ended | 12 Months Ended
--- | --- | ---
Jul. 31, 2017 | Mar. 31, 2017
Deferred Compensation Arrangement With Individual Share Based Payments [Line Items] |  |
Weighted-average Grant-Date Fair Value, Beginning Balance Outstanding | $ 24.19 | $ 23.58
Weighted-average Grant-Date Fair Value, Retirement distribution | $ 24.19 | 6.83
Weighted-average Grant-Date Fair Value, Ending Balance Outstanding |  | $ 24.19
Number of Shares Beginning Balance Outstanding | 350,838 | 363,630
Number of Shares, Retirement distribution | (350,838) | (12,792)
Number of Shares Ending Balance Outstanding |  | 350,838

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- Definition Share Based Compensation Arrangement by Share Based Payment Award Equity Instruments Other Than Options Retirement Distributions Weighted Average Grant Date Fair Value + References No definition available. + Details
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- Definition The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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