Retirement Plans (Narrative) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2018 USD ($) plan	Dec. 31, 2017 USD ($) plan
Defined Benefit Plan Disclosure
Net loss to be recognize during the next fiscal period | $	$ 125
Pension Plan
Defined Benefit Plan Disclosure
Defined contribution plan number	6
Pension Plan | United States
Defined Benefit Plan Disclosure
Number of retirement plans	3
Number of defined benefit plans	1
Defined contribution plan number	2
Accrued pension obligation | $	$ 4,249	$ 3,891
Pension Plan | Canada
Defined Benefit Plan Disclosure
Defined contribution plan number	2
Pension Plan | United Kingdom
Defined Benefit Plan Disclosure
Number of defined benefit plans		0
Defined contribution plan number	2
Defined benefit plans, estimated future employer contributions in current fiscal year | $	$ 250
Accrued pension obligation | $	$ 1,403	$ 1,431
Other Postretirement Benefits Plan
Defined Benefit Plan Disclosure
Service period	10 years
Other Postretirement Benefits Plan | Rail Technologies
Defined Benefit Plan Disclosure
Accrued pension obligation | $	$ 724	$ 1,104