Balance Sheet Information - USD ($) $ in Thousands	Jan. 31, 2020	Jan. 31, 2019
Accounts receivable, net:
Trade accounts	$ 56,978	$ 53,820
Unbilled receivables	6,954	1,391
Allowance for doubtful accounts	(1,380)	(739)
Accounts receivable, net	62,552	54,472
Inventories,net:
Finished goods	6,309	7,629
In process	3,287	1,103
Materials	44,303	45,344
Inventories, net	53,899	54,076
Other current assets:
Insurance policy benefit	38	336
Federal income taxes receivable	1,370	1,045
Receivable from sale of investments	0	1,055
Prepaid expenses and other	4,028	6,300
Other current assets	5,436	8,736
Property, plant and equipment, net:
Property, plant and equipment, net	100,850	106,615
Other assets:
Equity investments	1,289	345
Operating Lease right-of-use asset	4,275	0
Deferred income taxes	16	16
Other	1,507	2,963
Other assets	7,087	3,324
Accrued liabilities:
Salaries and related	4,188	8,244
Benefits	5,339	4,751
Insurance obligations	1,680	1,963
Warranties	2,019	890
Income taxes	293	328
Other taxes	1,734	2,434
Acquisition-related contingent liability, current	763	1,796
Lease liability, current	2,530	0
Other	2,197	3,072
Accrued liabilities	20,743	23,478
Other liabilities:
Postretirement benefits	8,741	7,678
Acquisition-related contingent consideration	2,171	2,376
Lease liability, noncurrent	2,627	0
Deferred income taxes	7,080	1,659
Uncertain tax positions	2,606	2,670
Other	5,936	3,852
Other liabilities	29,161	18,235
Land
Property, plant and equipment, net:
Property, plant and equipment, gross	3,117	3,234
Building and Improvements
Property, plant and equipment, net:
Property, plant and equipment, gross	80,330	81,381
Machinery and Equipment
Property, plant and equipment, net:
Property, plant and equipment, gross	158,354	155,463
Property, plant and equipment, Held-For-Use and assets Held-For-Sale
Property, plant and equipment, net:
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	141,832	133,724
Property, plant and equipment, net	100,850	106,354
Assets Held under Capital Leases
Property, plant and equipment, net:
Machinery and equipment	0	510
Capital leases, lessee balance dheet, assets by major class, accumulated depreciation	0	(249)
Assets owned and held under capital lease
Property, plant and equipment, net:
Property, plant and equipment, net	100,850	106,615
Leaseholds and Leasehold Improvements [Member]
Property, plant and equipment, net:
Property, plant and equipment, gross	$ 881	$ 0