Number of defined benefit plans offered by the company.

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Number of defined contribution plans offered by the company.

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Number of retirement plans offered by the company.

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- Definition

Amount of contribution received by defined benefit plan from employer which increases plan assets.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of cost (credit) included in accumulated other comprehensive (income) loss expected to be recognized in net periodic benefit cost (credit) for fiscal year following most recent annual statement of financial position.

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Amount of contributions expected to be received by defined benefit plan from employer in next fiscal year following latest fiscal year.

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Amount of liability, recognized in statement of financial position, for defined benefit pension and other postretirement plans, classified as noncurrent.

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Retirement Plans - Narrative (Details) $ in Thousands	12 Months Ended
Retirement Plans - Narrative (Details) $ in Thousands	Dec. 31, 2019 USD ($) plan	Dec. 31, 2018 USD ($)	Dec. 31, 2017 plan
Defined Benefit Plan Disclosure
Net loss to be recognize during the next fiscal period	$ 47
United States
Defined Benefit Plan Disclosure
Defined benefit plans, estimated future employer contributions in current fiscal year	$ 660
Pension Plan
Defined Benefit Plan Disclosure
Defined contribution plan number \| plan	6
Pension Plan \| United States
Defined Benefit Plan Disclosure
Number of retirement plans \| plan	3
Number of defined benefit plans \| plan	1
Defined contribution plan number \| plan	2
Accrued pension obligation	$ 3,449	$ 4,249
Defined benefit plan, contributions	$ 550	0
Pension Plan \| Canada
Defined Benefit Plan Disclosure
Defined contribution plan number \| plan	2
Pension Plan \| United Kingdom
Defined Benefit Plan Disclosure
Number of defined benefit plans \| plan			0
Defined contribution plan number \| plan	2
Defined benefit plans, estimated future employer contributions in current fiscal year	$ 318
Accrued pension obligation	1,811	1,403
Defined benefit plan, contributions	$ 314	271
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	$ 840	$ 724