Business Segments (Reconciliation of Significant Reconciling Items) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Segment Reporting Information [Line Items]
Net sales	$ 167,797	$ 162,248	$ 446,043	$ 441,505
Segment Profit	16,445	13,553	36,496	35,261
Rail Products Segment [Member]
Segment Reporting Information [Line Items]
Net sales	102,105	105,552	283,085	277,843
Segment Profit	11,533	9,713	23,685	21,749
Construction Products Segment [Member]
Segment Reporting Information [Line Items]
Net sales	49,907	49,320	119,100	129,828
Segment Profit	3,251	2,855	7,838	5,373
Tubular Products Segments [Member]
Segment Reporting Information [Line Items]
Net sales	15,785	7,376	43,858	33,834
Segment Profit	$ 1,661	$ 985	$ 4,973	$ 8,139