Fair Value Measures (Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Jan. 31, 2012 years	Jan. 31, 2011	Oct. 31, 2011
Fair Value Measures [Abstract]
Change in research and development expenses	$ 2.3	$ 0.2
Contingent consideration	2.8		4.3
Contingent consideration payable period (in years)	2
Business acquisition, contingent consideration, at fair value on acquisition date	0.7
Non-marketable equity securities, carrying value	$ 4.0