Investments in and Loans to Joint Ventures (Details 3) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Ohio Castings [Member]
Results of operations
Revenues	$ 83,872	$ 55,497	$ 74,687
Gross profit	8,277	2,993	6,522
Equity Method Investment, Net Income (Loss)	5,906	1,115	3,627
Axis [Member]
Results of operations
Revenues	69,667	53,944	59,303
Gross profit	5,496	5,645	5,390
Income (loss) before interest	4,496	4,724	4,465
Equity Method Investment, Net Income (Loss)	(390)	(652)	(1,345)
Amtek Railcar [Member]
Results of operations
Equity Method Investment, Net Income (Loss)		$ (5,600)	$ (2,100)