Income taxes (Details Textuals) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Oct. 31, 2011	Oct. 31, 2010	Oct. 31, 2009	Oct. 31, 2008
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	$ 74,915
Total unrecognized tax benefits impact the effective tax rate	2,517	4,019
Income Taxes (Textuals) [Abstract]
Earnings before income taxes of domestic operations	181,258	130,149	21,864
Foreign income tax expense benefit related to the utilization of loss carryforwards	682	1,876	5
Additional tax benefit relating to retroactive reinstatement of research credit	1,580
Favorable adjustment related to settlement with tax authorities	2,027
Recognized tax benefits		(10,243)
Additional tax charge		5,249
Remeasurement of unrecognized tax benefits			2,752
Benefit related to an adjustment to current tax year	387	388	515
Tax Benefit Related To Prior Tax Year			531
Total unrecognized tax benefits	2,576	4,078	3,969	7,685
Accrued interest expense related to unrecognized tax benefits	327	460
Earnings before income taxes of international operations	133,303	101,170	(149,055)
Undistributed earnings aggregated	391,679	340,354
Tax credit carryforwards which will expire in 2013 through 2017	645
Operating loss carryforwards which will Expire in 2012 through 2031	74,915
Indefinite carryforward period	575
Net change in the valuation allowance	1,442	2,081
Valuation allowance relates to tax credits and loss carryforwards	4,287
Minimum [Member]
Operating Loss Carryforwards [Line Items]
Decrease in unrecognized tax benefits	0
Total unrecognized tax benefits impact the effective tax rate	0
Maximum [Member]
Operating Loss Carryforwards [Line Items]
Decrease in unrecognized tax benefits	500
Total unrecognized tax benefits impact the effective tax rate	500
Federal [Member]
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	19,117
Income Taxes (Textuals) [Abstract]
Operating loss carryforwards which will Expire in 2012 through 2031	19,117
Foreign [Member]
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	575
Income Taxes (Textuals) [Abstract]
Operating loss carryforwards which will Expire in 2012 through 2031	575
State [Member]
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	55,798
Income Taxes (Textuals) [Abstract]
Operating loss carryforwards which will Expire in 2012 through 2031	$ 55,798