Taxes - Provision for Income Taxes and Effective Tax Rates (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Apr. 30, 2015	Apr. 30, 2014	Apr. 30, 2015	Apr. 30, 2014
Income Tax Disclosure [Abstract]
Income before income taxes	$ 83,884	$ 68,059	$ 160,499	$ 139,243
Provision (benefit) for income tax	$ 28,288us-gaap_IncomeTaxExpenseBenefit	$ 4,742us-gaap_IncomeTaxExpenseBenefit	$ 39,714us-gaap_IncomeTaxExpenseBenefit	$ 8,230us-gaap_IncomeTaxExpenseBenefit
Effective tax rate	33.70%	7.00%	24.70%	5.90%

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 12

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32687-109319

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 13

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32698-109319

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(h)(2))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph h

-Subparagraph 2

-Article 4

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Period Type:	duration