Property and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Property and equipment
Property and equipment, at cost	$ 397,771	$ 387,744
Less: accumulated depreciation	(290,466)	(271,416)
Property and equipment, net	107,305	116,328
Land
Property and equipment
Property and equipment, at cost	6,170	6,170
Buildings
Property and equipment
Property and equipment, at cost	28,693	28,925
Auto and trucks
Property and equipment
Property and equipment, at cost	27,945	27,444
Machinery and equipment
Property and equipment
Property and equipment, at cost	329,586	320,007
Assets in progress
Property and equipment
Property and equipment, at cost	4,129	3,950
Office and safety equipment
Property and equipment
Property and equipment, at cost	$ 1,248	$ 1,248

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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