Line of Credit (Details) (USD $) In Millions, unless otherwise specified			12 Months Ended
	Oct. 31, 2012	Jul. 31, 2012	Jul. 31, 2012 Unsecured Line of Credit [Member]	Jul. 31, 2012 Other Lines of Credit [Member]
Line of Credit Facility [Line Items]
Borrowing capacity			$ 32.5	$ 1.6
Interest rate, minimum (in hundredths)			2.50%	4.50%
Interest rate, maximum (in hundredths)			3.00%	5.00%
Amount outstanding	16.1	14.9
Letters of credit outstanding	1.5	4.1
Available borrowing capacity	$ 18.0