Summary of Net Accounts Receivable Due from Customers Accounted for 10% or More Account Receivable (Detail) (Accounts Receivable)	12 Months Ended
	Jul. 31, 2014	Jul. 31, 2013
Philips
Accounts Receivable [Line Items]
Percentage of net accounts receivable	16.00%	18.00%
L-3
Accounts Receivable [Line Items]
Percentage of net accounts receivable	16.00%	16.00%
Toshiba
Accounts Receivable [Line Items]
Percentage of net accounts receivable	11.00%		[1]

[1] Total net accounts receivable was less than 10% in this fiscal year.