Retirement Plans (Narrative) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014 contract	Mar. 31, 2013
Defined Benefit Plan Disclosure [Line Items]
Number of retirement plans	5
Defined Benefit Plan Number	3
Active Defined Benefit Plan Number	1
Inactive Defined Benefit Plan Number	2
Defined Contribution Plan Number	2
Defined Benefit Plans, Estimated Future Employer Contributions in Current Fiscal Year	$ 448
Defined Contribution Plan, Cost Recognized	675	578
Salaried Benefit Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Description of Postemployment Benefits	The Company has a domestic defined contribution plan that covers all non-union hourly and all salaried employees (Salaried Plan). The Salaried Plan permits both pre-tax and after-tax employee contributions. Participants can contribute, subject to statutory limitations, between 1% and 75% of eligible pre-tax pay and between 1% and 100% of eligible after-tax pay. The Company's employer match is 100% of the first 1% of deferred eligible compensation and up to 50% of the next 6%, based on years of service, of deferred eligible compensation, for a total maximum potential match of 4%. The Company may also make discretionary contributions to the Salaried Plan.
Defined Contribution Plan, Cost Recognized	556	449
Union Benefit Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Description of Postemployment Benefits	The Company also has a domestic defined contribution plan for union hourly employees with contributions made by both the participants and the Company based on various formulas (Union Plan).
Defined Contribution Plan, Cost Recognized	17	16
Canadian Employees [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Contribution Plan Number	2
Description of Postemployment Benefits	Rail Technologies, maintains a defined contribution plan covering all non-union employees at its Montreal, Quebec, Canada location (Montreal Plan). Under the terms of the Montreal Plan, the employer may contribute 4% of each employee's compensation as a non-elective contribution and may also contribute 30% of the first 6% of each employee's compensation contributed to the Montreal Plan.
United Kingdom Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plans, Estimated Future Employer Contributions in Current Fiscal Year	298
Defined Benefit Plan, Contributions by Employer	75
Description of Postemployment Benefits	The subsidiary also maintains a defined contribution plan covering substantially all employees at its United Kingdom locations (U.K. Plan). Benefits under the U.K. Plan are provided under no formal written agreement. Under the terms of the defined contribution U.K. Plan, the employer may make non-elective contributions of between 3% and 10% of each employee's compensation.
Defined Contribution Plan, Cost Recognized	$ 38	$ 33
Kelsan Benefit Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Description of Postemployment Benefits	Finally, Rail Technologies maintains a defined contribution plan covering substantially all of the employees at its Burnaby, British Columbia, Canada location (Burnaby Plan). Under the terms of the Burnaby Plan, the employer may contribute 4% of each employee's compensation as a non-elective contribution and may also contribute 30% of the first 6% of each employee's compensation contributed to the Burnaby Plan.The following table summarizes the expense associated with the contributions made to these plans.