Segment Reporting (Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Oct. 31, 2011	Oct. 31, 2010
10 Percent Of Net Sales [Member]
Segment Reporting Information [Line Items]
Number of major customers accounting for net sales	0	0
10 Percent Of Gross Accounts Receivable [Member]
Segment Reporting Information [Line Items]
Number of major customers accounting for gross accounts receivable	0	0
Industrial Products [Member]
Segment Reporting Information [Line Items]
Restructuring expenses		0.7