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Valuation and Qualifying Accounts (Parenthetical) (Detail) $ in Millions | 4 Months Ended
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Jul. 31, 2017 USD ($)
Fresh Start Accounting Adjustments |
Valuation and Qualifying Accounts Disclosure [Line Items] |
Deductions from allowance for doubtful accounts | $ 15.4

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- Definition Amount of direct write-downs of accounts receivable charged against the allowance. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919249-210447 + Details
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