Accounts Receivable (Details) - USD ($)	3 Months Ended	12 Months Ended
	Oct. 31, 2023	Jul. 31, 2023
Statement [Line Items]
Total accounts receivable	$ 186,983,000	$ 165,248,000
Less allowance for doubtful accounts	1,918,000	2,089,000
Accounts receivable, net	$ 185,065,000	$ 163,159,000
Accounts Receivable | Customer Concentration Risk | U.S. government
Statement [Line Items]
Concentration risk, percentage	35.00%	35.30%
Accounts Receivable | Customer Concentration Risk | AT&T, Inc.
Statement [Line Items]
Concentration risk, percentage		11.00%
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-05-01
Statement [Line Items]
Remaining performance obligations, period	24 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-11-01
Statement [Line Items]
Remaining performance obligations, period	1 year
Billed Receivables | Commercial and International Customers
Statement [Line Items]
Total accounts receivable	$ 53,001,000	$ 52,438,000
Billed Receivables | U.S. Government and Its Agencies
Statement [Line Items]
Total accounts receivable	19,269,000	31,149,000
Unbilled Receivables
Statement [Line Items]
Long-term receivables		2,993,000
Unbilled Receivables | Commercial and International Customers
Statement [Line Items]
Total accounts receivable	68,474,000	54,469,000
Unbilled Receivables | U.S. Government and Its Agencies
Statement [Line Items]
Total accounts receivable	$ 46,239,000	$ 27,192,000