Consolidated Condensed Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 11,757	$ 8,608
Restricted cash	654	672
Short-term investment securities	23,699	19,793
Accounts receivable, net of $152 and $210 of reserves, respectively	9,452	10,115
Inventories	20,336	19,513
Contract assets	8,787	9,107
Other current assets	1,956	1,466
Total current assets	76,641	69,274
Property, plant and equipment	46,480	45,661
Less: Accumulated depreciation	32,319	31,484
Net property, plant and equipment	14,161	14,177
Goodwill	13,804	13,714
Intangible assets	10,288	10,785
Operating lease right-of-use assets, net	6,115	6,701
Investment in partnerships	600	570
Long-term investment securities	2,765	5,085
Other assets, net	876	990
Total assets	125,250	121,296
Current liabilities:
Current financing leases	12	21
Current operating leases	2,108	2,156
Accounts payable	12,132	8,670
Accrued salaries, wages and commissions	3,915	3,581
Other accrued liabilities	4,297	4,235
Total current liabilities	22,464	18,663
Noncurrent operating leases	4,166	4,726
Other postretirement benefit obligations	374	385
Accrued pension liabilities	834	907
Deferred tax liabilities, net	1,028	1,018
Other long-term liabilities	4,139	4,398
Total liabilities	33,005	30,097
Commitments and contingencies (Note 11)
Shareholders' equity:
Common stock, $1.00 par value per share; 20,000 shares authorized; 8,999 and 8,951 shares issued and outstanding at March 31, 2021 and December 31, 2020, respectively	8,999	8,951
Additional paid-in capital	89,926	89,702
Accumulated deficit	(6,096)	(6,810)
Accumulated other comprehensive loss	(527)	(679)
Total shareholders' equity	92,302	91,164
Non-controlling interest	(57)	35
Total equity	92,245	91,199
Total liabilities and equity	$ 125,250	$ 121,296