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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

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