Business Segments and Geographic Information (Details Textual) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012
Schedule of Equity Method Investments [Line Items]
Number of reportable business segment			4
Equity in earnings (losses) of affiliates, net of income tax provision	$ 1,526,000	$ 474,000	$ 3,772,000	$ 1,652,000
SACS
Schedule of Equity Method Investments [Line Items]
Ownership percentage in Entity			50.00%
Equity in earnings (losses) of affiliates, net of income tax provision	1,300,000	1,400,000	3,800,000	4,000,000
Investment in Joint Ventures	8,700,000		8,700,000		7,800,000
Geo Amey
Schedule of Equity Method Investments [Line Items]
Ownership percentage in Entity			50.00%
Equity in earnings (losses) of affiliates, net of income tax provision	200,000	(900,000)	(100,000)	(2,300,000)
Investment in Joint Ventures	$ (4,200,000)		$ (4,200,000)		$ (4,100,000)