Accounts Receivable (Tables)

12 Months Ended

Jul. 31, 2018

Accounts receivable consist of the following at July 31, 2018 and 2017:



	2018		2017
Billed receivables from commercial and international customers	$	83,411,000	71,404,000
Unbilled receivables from commercial and international customers	19,731,000		24,668,000
Billed receivables from the U.S. government and its agencies	26,251,000		18,497,000
Unbilled receivables from the U.S government and its agencies	19,807,000		11,693,000
Total accounts receivable	149,200,000		126,262,000
Less allowance for doubtful accounts	1,761,000		1,300,000
Accounts receivable, net	$	147,439,000	124,962,000