Accrued Expenses and Other Current Liabilities (Product Warranty Rollforward) (Details)	12 Months Ended
Jul. 31, 2018 USD ($) credit	Jul. 31, 2017 USD ($)	Jul. 31, 2018 USD ($)
Business Acquisition [Line Items]
Minimum coverage period of product warranty from the date of shipment	1 year
Changes in Product Warranty Liability
Accrued warranty obligations, as of the beginning of the period	$ 17,617,000	$ 15,362,000
Provision for warranty obligations	5,055,000	5,394,000
Adjustment to TCS pre-acquisition contingent liability	0	4,200,000
Charges incurred	(8,244,000)	(7,339,000)
Warranty settlement and reclass (see below)	(2,690,000)	0
Accrued warranty obligations, as of the end of the period	11,738,000	17,617,000
Accrued warranty obligations	17,617,000	15,362,000	$ 11,738,000
TCS's 911 call handling software \| TeleCommunication Systems, Inc.
Changes in Product Warranty Liability
Accrued warranty obligations, as of the beginning of the period	9,909,000
Accrued warranty obligations, as of the end of the period	4,650,000	9,909,000
Accrued warranty obligations	$ 9,909,000	$ 9,909,000	4,650,000
Full and final warrant settlement with AT&T \| TCS's 911 call handling software \| TeleCommunication Systems, Inc.
Changes in Product Warranty Liability
Number of monthly credits issued \| credit	36
Amount of monthly credit			153,000
Present value of monthly credits			3,616,000
Cost of Sales \| Full and final warrant settlement with AT&T \| TCS's 911 call handling software \| TeleCommunication Systems, Inc.
Changes in Product Warranty Liability
Benefit in connection with favorable settlement	$ 660,000
Accounts payable and accrued liabilities \| Full and final warrant settlement with AT&T \| TCS's 911 call handling software \| TeleCommunication Systems, Inc.
Changes in Product Warranty Liability
Present value of monthly credits			1,586,000
Other noncurrent liabilities \| Full and final warrant settlement with AT&T \| TCS's 911 call handling software \| TeleCommunication Systems, Inc.
Changes in Product Warranty Liability
Present value of monthly credits			$ 2,030,000

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Total number of monthly credits issued pursuant to the terms and conditions of a full and final warranty settlement

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Amount of monthly credit pursuant to the terms and conditions of a full and final warranty settlement

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Product Warranty, Favorable Settlement Adjustment

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Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers.

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Amount of increase in the standard and extended product warranty accrual from a business acquisition.

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Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers. For classified balance sheets, represents the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Amount of increase (decrease) in the standard and extended product warranty accrual from changes in estimates attributable to preexisting product warranties.

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