Commitments and Contingent Liabilities (Narratives) (Details) $ in Thousands		12 Months Ended							72 Months Ended
	Mar. 13, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2015 tie	Dec. 31, 2014 USD ($)	Dec. 31, 2013 tie	Dec. 31, 2012 USD ($)	Dec. 31, 2011	Dec. 31, 2011 tie
Product Liability Contingency
Accrued warranty		$ 2,057	$ 8,682
Amounts reclassified to accrued settlement		6,600
Number of concrete ties manufactured | tie									3,000,000.0
Legal fees		43,400	0
Accrued legal settlement, current		10,000
Accrued legal settlement, non-current		40,000
Present value or proposed remedial work		1,100,000
Undiscovered remedial work		1,700,000
Subsequent Event | Uprr
Product Liability Contingency
Purchase commitment	$ 48,000
Annual commitment amount	8,000
2005 Contract
Product Liability Contingency
Warranty period							15 years
Uprr
Product Liability Contingency
Amounts reclassified to accrued settlement		6,600
Legal fees		43,400
Uprr | Subsequent Event
Product Liability Contingency
Litigation settlement amount	50,000
Litigation settlement amount, current	2,000
Litigation settlement amount, non-current	$ 48,000
Uprr | 2005 Contract
Product Liability Contingency
Product warranty expense							$ 22,000
Number of concrete ties manufactured | tie									1,600,000
Warranty ratio							1	1.5
Warranty period				10 years			15 years	5 years
Litigation settlement amount							$ 12,000
Ties manufactured that did not meet criteria to be covered as warranty replacement ties | tie				90,100		170,000
Cure period to claim					90 days	90 days
Change in standard product warranty accrual					$ 8,766
Uprr | 2005 Contract | Previously Reported
Product Liability Contingency
Warranty ratio							1.5
Warranty period							5 years
Rail Products and Services
Product Liability Contingency
Product warranty expense			611
Tubular and Energy Services
Product Liability Contingency
Product warranty expense		839
Reserve for concrete ties
Product Liability Contingency
Accrued warranty		531	7,595
Product warranty expense		$ 136	$ 21
Warranty period							5 years