Accounts Receivable (Tables)

6 Months Ended

Jan. 31, 2023

Receivables [Abstract]

Accounts receivable

Accounts receivable consist of the following at:

	January 31, 2023		July 31, 2022
Receivables from commercial and international customers	$	63,169,000	59,922,000
Unbilled receivables from commercial and international customers	45,450,000		39,826,000
Receivables from the U.S. government and its agencies	23,370,000		24,776,000
Unbilled receivables from the U.S. government and its agencies	5,736,000		1,524,000
Total accounts receivable	137,725,000		126,048,000
Less allowance for doubtful accounts	2,803,000		2,337,000
Accounts receivable, net	$	134,922,000	123,711,000