Accounts Receivable (Tables)

6 Months Ended

Jan. 31, 2016

Accounts Receivable Additional Disclosures [Abstract]

Accounts receivable

Accounts receivable consist of the following at:

	January 31, 2016		July 31, 2015
Billed receivables from commercial customers	$	27,677,000	39,062,000
Billed receivables from the U.S. government and its agencies	15,124,000		8,375,000
Unbilled receivables on contracts-in-progress	12,629,000		23,024,000
Total accounts receivable	55,430,000		70,461,000
Less allowance for doubtful accounts	1,681,000		1,206,000
Accounts receivable, net	$	53,749,000	69,255,000