Accounts Receivable (Tables)

3 Months Ended

Oct. 31, 2013

Accounts Receivable Additional Disclosures [Abstract]

Accounts receivable

Accounts receivable consist of the following at:

	October 31, 2013		July 31, 2013
Billed receivables from commercial customers	$	46,722,000	40,005,000
Billed receivables from the U.S. government and its agencies	8,353,000		8,114,000
Unbilled receivables on contracts-in-progress	7,652,000		2,399,000
Total accounts receivable	62,727,000		50,518,000
Less allowance for doubtful accounts	707,000		603,000
Accounts receivable, net	$	62,020,000	49,915,000