Earnings Per Share - Reconciliation of Shares Used to Calculate Basic and Diluted Earnings Per Share (Detail)	3 Months Ended	6 Months Ended
Apr. 30, 2015	Apr. 30, 2014	Apr. 30, 2015	Apr. 30, 2014
Class A Common Stock [Member]
Class of Stock [Line Items]
Basic shares	25,678,393	25,540,341	25,643,139	25,505,348
Assumed conversion of stock options	10,260	20,505	9,657	20,388
Diluted shares	25,688,653	25,560,846	25,652,796	25,525,736
Class B Common Stock [Member]
Class of Stock [Line Items]
Basic shares	22,100,000	22,100,000	22,100,000	22,100,000
Diluted shares	22,100,000	22,100,000	22,100,000	22,100,000
Basic and diluted shares	22,119,966	22,119,966	22,119,966	22,119,966

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The sum of dilutive potential common shares or units used in the calculation of the diluted per-share or per-unit computation.

+ References

+ Details

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- Definition

The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

+ References

+ Details

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- Definition

Average number of shares or units issued and outstanding that are used in calculating basic and diluted earnings per share (EPS).

+ References

No definition available.

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- Definition

Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 260

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 260

-SubTopic 10

-Section 45

-Paragraph 10

-URI http://asc.fasb.org/extlink&oid=7655603&loc=d3e1448-109256

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Weighted-Average Number of Common Shares Outstanding

-URI http://asc.fasb.org/extlink&oid=6528421

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