Retirement, pension and other postretirement plans (Details15) (USD $) In Thousands, unless otherwise specified	Oct. 31, 2011
With Medicare Part D US Subsidy [Member]
Retiree pension benefit payments
2012	$ 2,123
2013	2,316
2014	2,693
2015	2,955
2016	3,238
2017-2021	18,483
Without Medicare Part D US Subsidy [Member]
Retiree pension benefit payments
2012	1,872
2013	2,013
2014	2,345
2015	2,556
2016	2,787
2017-2021	15,279
Postretirement Benefit Plans International [Member]
Retiree pension benefit payments
2012	4
2013	4
2014	8
2015	16
2016	17
2017-2021	$ 115

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The amount of the aggregate benefits expected to be paid in the five fiscal years thereafter (the aggregate amount of benefits expected to be paid in years 6 through 10 after the date of the latest statement of financial position).

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

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- Definition

The amount of the benefits expected to be paid in Year 5.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

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- Definition

The amount of the benefits expected to be paid in Year 4.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

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- Definition

The amount of the benefits expected to be paid in Year 1.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

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- Definition

The amount of the benefits expected to be paid in Year 3.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

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- Definition

The amount of the benefits expected to be paid in Year 2.

+ References

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

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-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

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