Operating segments (Details 1) (USD $) In Thousands	3 Months Ended	9 Months Ended
Jul. 31, 2011	Jul. 31, 2010	Jul. 31, 2011	Jul. 31, 2010
Reconciliation of Revenue from Segments to Consolidated [Abstract]
Total profit for reportable segments	$ 78,656	$ 67,695	$ 236,608	$ 161,555
Interest expense	(827)	(1,580)	(3,560)	(4,661)
Interest and investment income	190	170	430	649
Other - net	169	177	2,896	700
Income before income taxes	$ 78,188	$ 66,462	$ 236,374	$ 158,243

Sum of operating profit and nonoperating income (expense) before income (loss) from equity method investments, income taxes, extraordinary items, cumulative effects of changes in accounting principles, and noncontrolling interest.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 08
-Paragraph h
-Subparagraph 1(i)
-Article 4

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The cost of borrowed funds accounted for as interest that was charged against earnings during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 34
-Paragraph 21

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher OTS
-Name Federal Regulation (FR)
-Number Title 12
-Chapter V
-Section 563c.102
-Paragraph 9
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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-Name Regulation S-X (SX)
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Income derived from investments in debt securities and on cash and cash equivalents the earnings of which reflect the time value of money or transactions in which the payments are for the use or forbearance of money.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Statement of Financial Accounting Standard (FAS)
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-Paragraph 14

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Regulation S-X (SX)
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-Paragraph 7
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The net result for the period of deducting operating expenses from operating revenues.

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The net amount of other nonoperating income and expense, which does not qualify for separate disclosure on the income statement under materiality guidelines.

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