Reporting Segments Total depreciation and amortization by reporting segment (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Segment Reporting Information [Line Items]
Total depreciation and amortization	$ 10,346	$ 10,265	$ 11,008
GETS [Member]
Segment Reporting Information [Line Items]
Total depreciation and amortization	5,730	5,171	5,761
PSS [Member]
Segment Reporting Information [Line Items]
Total depreciation and amortization	893	840	1,210
MRI [Member]
Segment Reporting Information [Line Items]
Total depreciation and amortization	415	538	400
Corporate [Member]
Segment Reporting Information [Line Items]
Total depreciation and amortization	$ 3,308	$ 3,716	$ 3,637