Accounts Receivable (Tables)

9 Months Ended

Apr. 30, 2015

Accounts Receivable Additional Disclosures [Abstract]

Accounts receivable

Accounts receivable consist of the following at:

	April 30, 2015		July 31, 2014
Billed receivables from commercial customers	$	27,340,000	31,681,000
Billed receivables from the U.S. government and its agencies	11,259,000		10,316,000
Unbilled receivables on contracts-in-progress	29,779,000		13,517,000
Total accounts receivable	68,378,000		55,514,000
Less allowance for doubtful accounts	757,000		627,000
Accounts receivable, net	$	67,621,000	54,887,000