Select balance sheet data - Schedule of Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
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Total property, plant and equipment, gross	$ 446,236	$ 427,352
Less accumulated depreciation	292,950	270,824
Total property, plant and equipment, net	153,286	156,528
Land
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Total property, plant and equipment, gross	2,564	2,564
Land improvements
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Total property, plant and equipment, gross	$ 4,740	4,261
Land improvements | Minimum
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Property, plant and equipment useful lives	15 years
Land improvements | Maximum
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Property, plant and equipment useful lives	39 years
Building and building improvements
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Total property, plant and equipment, gross	$ 80,286	79,553
Building and building improvements | Minimum
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Property, plant and equipment useful lives	15 years
Building and building improvements | Maximum
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Property, plant and equipment useful lives	39 years
Machinery, equipment and tooling
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Total property, plant and equipment, gross	$ 325,387	310,300
Machinery, equipment and tooling | Minimum
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Property, plant and equipment useful lives	3 years
Machinery, equipment and tooling | Maximum
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Property, plant and equipment useful lives	10 years
Vehicles
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Total property, plant and equipment, gross	$ 4,978	4,377
Property, plant and equipment useful lives	5 years
Office furniture and fixtures
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Total property, plant and equipment, gross	$ 25,420	23,034
Office furniture and fixtures | Minimum
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Property, plant and equipment useful lives	3 years
Office furniture and fixtures | Maximum
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Property, plant and equipment useful lives	7 years
Construction in progress
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Total property, plant and equipment, gross	$ 2,861	$ 3,263