Fair Value Measures (Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended	12 Months Ended
	Jul. 31, 2011	Jul. 31, 2011	Oct. 31, 2010 years
Fair Value Measures
Contingent consideration	$ 4.2	$ 4.2
Contingent consideration payable period (years)			3
Changes in Research and Development Expenses	0.4	3.8
Non-marketable equity securities, cost	2.4	2.4
Non-marketable equity securities, sold	3.2
Non-marketable equity securities, gain	0.8
Non-marketable equity securities, carrying value	4.0	4.0
Business Acquisition, Contingent Consideration, at Fair Value			$ 7.8