Note 2 (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
Apr. 30, 2013	Apr. 30, 2012	Apr. 30, 2013	Apr. 30, 2012
Allocated Share-based Compensation Expense	$ 1.3	$ 1.7	$ 2.5	$ 2.9
Allocated Share-based Compensation Expense, Net of Tax		1.3
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value	$ 0.7	$ 1.6	$ 1.5	$ 2.6

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section F

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 14.F)

-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (h)(1)(i)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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