Unaudited Condensed Consolidated Statements Of Comprehensive Income (Parenthetical) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Apr. 30, 2015	Apr. 30, 2014	Apr. 30, 2015	Apr. 30, 2014
Statement of Comprehensive Income [Abstract]
Deferred gains (losses), tax	$ 668	$ (873)	$ 5,513	$ 456
Reclassification adjustment on deferred (gains) losses included in net income, tax	(3,018)	(1,798)	(3,408)	(1,504)
Changes in unrealized gains (losses) on available-for-sale securities, tax	$ 0	$ 0	$ 0	$ 0

Amount of tax expense (benefit) after reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities.

No definition available.

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- Definition

Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income of accumulated gain (loss) realized from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's deferred hedging gain (loss).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 12

-URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e640-108580

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4

-Subparagraph c

-URI http://asc.fasb.org/extlink&oid=35706170&loc=d3e41638-113959

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- Definition

Amount of tax expense (benefit), before reclassification adjustments, related to increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 10A

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=36458714&loc=SL7669646-108580

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 12

-URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e640-108580

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