Investments in and Loans to Joint Ventures (Details 1) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Ohio Castings [Member]
Results of operations
Revenues	$ 13,654	$ 23,388
Gross profit	210	2,048
Net earnings/(loss)	(598)	1,132
Axis [Member]
Results of operations
Revenues	16,411	20,340
Gross profit	5,042	5,063
Income (loss) before interest	4,768	4,789
Net earnings/(loss)	$ 3,854	$ 3,664