Commitments and Contingent Liabilites (Narrative) (Details) $ in Thousands, item in Millions	3 Months Ended		12 Months Ended					168 Months Ended
	Dec. 31, 2014 USD ($)	Jun. 30, 2014 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)	Dec. 31, 2012 USD ($)	Dec. 31, 2011 item	Dec. 31, 2011 item
Product Liability Contingency [Line Items]
Concrete Ties Manufactured | item								3.0
Product Warranty Expense	$ 4,766	$ 4,000
Standard Product Warranty Accrual	11,500		$ 8,755	$ 11,500
Accrual for Environmental Loss Contingencies	3,344		6,640	3,344
Reserve for Concrete Ties [Member]
Product Liability Contingency [Line Items]
Litigation Settlement, Amount						$ 12,000
Product Warranty Expense			972	9,854	$ 612	$ 22,000
Standard Product Warranty Accrual	$ 10,331		$ 7,544	10,331
Standard Product Warranty Accrual, Period Increase (Decrease)				$ 8,766
The UPRR [Member]
Product Liability Contingency [Line Items]
Concrete Ties Manufactured | item							1.6