Reporting Segments Capital expenditure data by reporting segment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Segment Reporting Information [Line Items]
Total purchases of property and equipment	$ 7,940	$ 8,774	$ 7,529
GETS [Member]
Segment Reporting Information [Line Items]
Total purchases of property and equipment	4,594	5,685	4,832
PSS [Member]
Segment Reporting Information [Line Items]
Total purchases of property and equipment	2,046	2,008	670
MRI [Member]
Segment Reporting Information [Line Items]
Total purchases of property and equipment	153	38	29
Corporate [Member]
Segment Reporting Information [Line Items]
Total purchases of property and equipment	$ 1,147	$ 1,043	1,998
Including L R Kimball and DSPCon Property and Equipment Acquired [Member]
Segment Reporting Information [Line Items]
Total purchases of property and equipment			$ 7,529