Other Expense (Income) (Details) $ in Thousands	12 Months Ended
Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Jun. 19, 2018 a
Condensed Income Statements, Captions
Foreign currency losses (gains)	$ 202	$ (483)
Other	(1,404)	(508)
Other income	(4,492)	461
Proceeds from the sale of property, plant, and equipment	1,151	2,389
Disposal Group, Disposed of by Sale, Not Discontinued Operations \| Land in Willis, TX
Condensed Income Statements, Captions
Loss on U.S. pension settlement (a)	2,210	0
Tubular and Energy Services \| Disposal Group, Disposed of by Sale, Not Discontinued Operations \| Land in Willis, TX
Condensed Income Statements, Captions
Loss on Construction Segment relocation and closure activities (b)	1,768	0
Area of land (in acres) \| a			54.5
Proceeds from the sale of property, plant, and equipment		2,047
Tubular and Energy Services \| Disposal Group, Disposed of by Sale, Not Discontinued Operations \| Ball Winch Field Service
Condensed Income Statements, Captions
Loss on Tubular and Energy Segment asset sale (d)	0	269
Rail Products and Services
Condensed Income Statements, Captions
Loss on Tubular and Energy Segment closure activities (c)	1,716	0
Gain on prior Rail Segment warranty claim (f)	0	(525)
Rail Products and Services \| Disposal Group, Disposed of by Sale, Not Discontinued Operations
Condensed Income Statements, Captions
Loss on Tubular and Energy Segment fixed asset sales or disposals (e)	$ 0	$ 786

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Amount of payment, which decreases plan assets of defined benefit plan, for irrevocable action relieving primary responsibility for benefit obligation and eliminating risk for obligation and assets used to effect settlement. Transaction constituting settlement includes, but is not limited to, making lump-sum cash payment to participant in exchange for their rights to receive specified benefits and purchasing nonparticipating annuity contract.

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Amount of gain (loss) on sale or disposal of assets, including but not limited to property plant and equipment, intangible assets and equity in securities of subsidiaries or equity method investee.

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