Share-Based Compensation Plans - Employee Stock Purchase Plan (Details) - Employee Stock Purchase Plan - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Oct. 31, 2015	Oct. 31, 2014	Oct. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average fair value of granted purchase rights per share (usd per share)	$ 1.5	$ 1.4	$ 1.1
Common stock issued	0.2	0.2	0.2
Fair value of common stock issued per share (usd per share)	$ 28.8	$ 25.8	$ 21.3
Aggregate purchases	$ 4.7	$ 4.3	$ 4.0