Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Jul. 31, 2026	Jan. 31, 2026	Jul. 31, 2025
Property, Plant, and Equipment [Line Items]
Property, plant and equipment, gross	$ 182,048	$ 180,324	$ 179,682
Less accumulated depreciation and amortization	(148,652)	(145,746)	(143,562)
Property, plant and equipment, net	33,396	34,578	36,120
Land
Property, Plant, and Equipment [Line Items]
Property, plant and equipment, gross	3,731	3,731	3,731
Land improvements
Property, Plant, and Equipment [Line Items]
Property, plant and equipment, gross	706	706	706
Buildings and building improvements
Property, Plant, and Equipment [Line Items]
Property, plant and equipment, gross	52,059	52,059	52,050
Machinery and equipment
Property, Plant, and Equipment [Line Items]
Property, plant and equipment, gross	124,903	123,179	122,538
Leasehold improvements
Property, Plant, and Equipment [Line Items]
Property, plant and equipment, gross	$ 649	$ 649	$ 657