Accounts Receivable (Tables)

3 Months Ended

Oct. 31, 2015

Accounts Receivable Additional Disclosures [Abstract]

Accounts receivable

Accounts receivable consist of the following at:

	October 31, 2015		July 31, 2015
Billed receivables from commercial customers	$	29,977,000	39,062,000
Billed receivables from the U.S. government and its agencies	11,645,000		8,375,000
Unbilled receivables on contracts-in-progress	19,564,000		23,024,000
Total accounts receivable	61,186,000		70,461,000
Less allowance for doubtful accounts	1,836,000		1,206,000
Accounts receivable, net	$	59,350,000	69,255,000