Restructuring And Asset Impairment (Schedule Of Restructuring Expense) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Oct. 31, 2011	Oct. 31, 2010
Restructuring Cost and Reserve [Line Items]
Restructuring expenses		$ 759
Cost Of Sales [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring expenses		20
Operating Expenses [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring expenses		$ 739