Contingencies (Details) (USD $) In Thousands	Jul. 31, 2011	Oct. 31, 2010
Contingencies (Textuals) [Abstract]
Accrual for the ongoing operation, maintenance and monitoring obligation at the Site	$ 795	$ 885

Total costs accrued as of the balance sheet date for environmental loss contingencies.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Statement of Position (SOP)
-Number 96-1
-Paragraph 161
-Subparagraph a

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 5
-Paragraph 9

Name:	us-gaap_AccrualForEnvironmentalLossContingencies
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant