Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 24,234	$ 3,743
Receivables, net	26,428	28,648
Inventories	18,642	18,276
Prepaid expenses	2,560	2,304
Refundable income taxes	0	279
Total current assets	71,864	53,250
Property, plant, and equipment	118,388	116,089
Less accumulated depreciation and amortization	(64,633)	(59,350)
Net property, plant and equipment	53,755	56,739
Goodwill	51,838	51,838
Intangible assets, net	19,718	20,975
Non-qualified deferred compensation plan	3,724	2,775
Finance lease right of use assets	100	0
Operating lease right of use assets	2,052	3,034
Other assets	153	147
Total assets	203,204	188,758
Current liabilities:
Accounts payable	4,121	4,577
Accrued expenses	7,944	8,483
Deferred revenue	1,887	2,574
Finance lease liabilities	15	0
Operating lease liabilities	1,154	1,150
Income taxes payable	16	0
Total current liabilities	15,137	16,784
Deferred income taxes	5,057	4,921
Non-qualified deferred compensation plan	3,810	2,788
Finance lease liabilities	86	0
Operating Lease, Liability, Noncurrent	950	1,940
Other liabilities	1,271	334
Total liabilities	26,311	26,767
Commitments and contingencies (Note 14)
Stockholders’ equity:
Preferred stock, $.01 par value, 1,000,000 shares authorized; no shares issued	0	0
Common stock, $.01 par value, 20,000,000 shares authorized; 7,529,625 and 7,500,066 shares issued and outstanding, respectively at December 31, 2020; and 7,475,768 and 7,446,209 shares issued and outstanding, respectively, at December 31, 2019	75	74
Additional paid-in capital	32,484	30,952
Retained earnings	144,921	131,552
Treasury stock at cost, 29,559 shares at December 31, 2020 and 2019	(587)	(587)
Total stockholders' equity	176,893	161,991
Total liabilities and stockholders' equity	$ 203,204	$ 188,758