Segment Reporting Deprecation and Amortization Expense (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Segment Reporting Information [Line Items]
Depreciation	$ 2,235	$ 1,649	$ 6,380	$ 4,956
Amortization expense	958	1,096	3,101	3,266
Mobile Connectivity [Member]
Segment Reporting Information [Line Items]
Depreciation	1,842	1,339	5,212	4,212
Amortization expense	958	1,096	3,101	3,266
Intertial Navigation [Member]
Segment Reporting Information [Line Items]
Depreciation	260	293	766	687
Amortization expense	0	0	0	0
Other Segments [Member]
Segment Reporting Information [Line Items]
Depreciation	133	17	402	57
Amortization expense	$ 0	$ 0	$ 0	$ 0