Earnings Per Share - Computation of Class Based Basic and Diluted Earnings Per Share (Detail)	12 Months Ended
Oct. 31, 2017
Class A Common Stock
Class of Stock [Line Items]
Basic and Diluted EPS, class based	40.00%
Class B Common Stock
Class of Stock [Line Items]
Basic and Diluted EPS, class based	60.00%

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.

No definition available.

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration