Income Taxes (Narrative) (Details) - USD ($)	5 Months Ended	7 Months Ended	12 Months Ended
	Dec. 31, 2017	Jul. 31, 2018	Jul. 31, 2018	Jul. 31, 2017	Jul. 31, 2016
Operating Loss Carryforwards [Line Items]
Income tax rate	35.00%	21.00%	27.00%	35.00%	35.00%
Estimated net discrete tax benefit from Tax Reform			$ 11,792,000
Federal alternative minimum tax credit		$ 3,243,000	3,243,000	$ 2,652,000
Federal, state and foreign research and experimentation credits		18,816,000	18,816,000	16,286,000
Minimum taxable income in the future to fully utilize net deferred tax assets		158,700,000	158,700,000
Unrecognized Tax Benefits, Including Interest		9,339,000	9,339,000	8,681,000
Interest accrued relating to income taxes		202,000	202,000	95,000
Unrecognized tax benefits that would positively impact our effective tax rate, if recognized		8,563,000	8,563,000	7,727,000
Income Taxes Payable, Noncurrent
Operating Loss Carryforwards [Line Items]
Unrecognized Tax Benefits, Including Interest		2,572,000	2,572,000	2,515,000
Deferred Tax Liability Noncurrent
Operating Loss Carryforwards [Line Items]
Unrecognized Tax Benefits, Including Interest		6,767,000	6,767,000	$ 6,166,000
Domestic Tax Authority
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards		19,069,000	19,069,000
Federal alternative minimum tax credit		3,243,000	3,243,000
Federal, state and foreign research and experimentation credits		10,948,000	10,948,000
Domestic Tax Authority | Generated From Current Fiscal Year Operations
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards		464,000	464,000
Domestic Tax Authority | Xypoint
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards		183,000	183,000
Domestic Tax Authority | TeleCommunication Systems, Inc.
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards		18,422,000	18,422,000
State and Local Jurisdiction
Operating Loss Carryforwards [Line Items]
Federal, state and foreign research and experimentation credits		6,982,000	6,982,000
Valuation allowance		6,771,000	6,771,000
State and local operating loss carryforwards		3,345,000	3,345,000
Operating loss carryforwards, valuation allowance		$ 3,138,000	$ 3,138,000