Accrued Expenses and Other Current Liabilities (Details) - USD ($)	Oct. 31, 2018	Jul. 31, 2018	Oct. 31, 2017	Jul. 31, 2017
Business Acquisition [Line Items]
Accrued wages and benefits	$ 22,506,000	$ 23,936,000
Accrued contract costs	13,285,000	10,016,000
Accrued warranty obligations	9,982,000	11,738,000	$ 13,001,000	$ 17,617,000
Accrued legal costs	6,946,000	6,179,000
Accrued commissions and royalties	4,605,000	4,654,000
Other	11,485,000	8,511,000
Accrued expenses and other current liabilities	68,809,000	65,034,000
TeleCommunication Systems Inc. | Pre-Acquisition Contingencies Related to TCS Intellectual Property
Business Acquisition [Line Items]
Accrued legal costs	$ 3,314,000	$ 3,372,000