Segment Reporting (Details Textual) - Segment	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Segment Reporting Information [Line Items]
Number of Reportable Segments	2
Mobile Connectivity [Member] | Mobile Comm Product Sales [Member]
Segment Reporting Information [Line Items]
Percent of Consolidated Net Sales	23.00%	23.00%	25.00%
Mobile Connectivity [Member] | VSAT Airtime Service Sales [Member]
Segment Reporting Information [Line Items]
Percent of Consolidated Net Sales	37.00%	35.00%	35.00%
Mobile Connectivity [Member] | Training and Content Sales [Member]
Segment Reporting Information [Line Items]
Percent of Consolidated Net Sales	20.00%	21.00%	14.00%
Intertial Navigation [Member] | FOG System Sales [Member]
Segment Reporting Information [Line Items]
Percent of Consolidated Net Sales	10.00%	10.00%	12.00%
Intertial Navigation [Member] | TACNAV System Sales [Member]
Segment Reporting Information [Line Items]
Percent of Consolidated Net Sales	8.00%	8.00%	11.00%
Non-US [Member]
Segment Reporting Information [Line Items]
Percent of consolidated long-lived tangible assets (less than)	10.00%	10.00%
Percent of Consolidated Net Sales	63.00%	67.00%	58.00%
CANADA
Segment Reporting Information [Line Items]
Percent of Consolidated Net Sales	11.00%	10.00%