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Summary of Cash-Based Performance Plan Unit Activity (Detail) - Predecessor - $ / shares | 4 Months Ended | 12 Months Ended
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Jul. 31, 2017 | Mar. 31, 2017
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |
Weighted-average Grant-Date Fair Value, Beginning Balance Outstanding | $ 24.19 | $ 23.58
Weighted-average Grant-Date Fair Value, Ending Balance Outstanding |  | $ 24.19
Number of Shares Beginning Balance Outstanding | 350,838 | 363,630
Number of Shares Ending Balance Outstanding |  | 350,838
Cash-based Performance Plan |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |
Weighted-average Grant-Date Fair Value, Beginning Balance Outstanding | $ 1.16 | $ 1.16
Weighted-average Grant-Date Fair Value, Cancelled/forfeited | $ 1.16 | 1.15
Weighted-average Grant-Date Fair Value, Ending Balance Outstanding |  | $ 1.16
Number of Shares Beginning Balance Outstanding | 7,733,725 | 7,913,716
Number of Shares, Cancelled/forfeited | (7,733,725) | (179,991)
Number of Shares Ending Balance Outstanding |  | 7,733,725

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- Definition The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period. + 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)(1)(iv)(3) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event. + 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)(iii)(3) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + 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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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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