CONSOLIDATED BALANCE SHEETS - USD ($)	Dec. 31, 2020	Dec. 31, 2019
Current Assets:
Cash and cash equivalents	$ 22,450,000	$ 45,048,000
Short-term investments	19,258,000	23,766,000
Accounts receivable, net of allowance for doubtful accounts of $41 and $36 in 2020 and 2019, respectively	16,445,000	18,886,000
Inventories	50,298,000	42,093,000
Prepaid expenses and other current assets	3,868,000	2,545,000
Total Current Assets	112,319,000	132,338,000
Long-term investments	46,207,000	31,772,000
Property, Plant and Equipment	218,912,000	200,990,000
Less: accumulated depreciation	123,977,000	116,384,000
Total Eqiupment	94,935,000	84,606,000
Other Assets and Deferred Charges:
Patents and licenses, net of accumulated amortization of $12,419 and $12,301 in 2020 and 2019, respectively	1,421,000	1,539,000
Goodwill	9,730,000	9,730,000
Other	2,278,000	2,046,000
Total Non- Current Assets	13,429,000	13,315,000
Total Assets	266,890,000	262,031,000
Current Liabilities:
Accounts payable	6,635,000	5,707,000
Accrued liabilities	6,565,000	5,148,000
Accrued income and other taxes	436,000	419,000
Total Current Liabilities	13,636,000	11,274,000
Line of credit	0	0
Other Liabilities and Deferred Credits:
Deferred income taxes	10,768,000	8,496,000
Other	2,044,000	4,391,000
Other Liabilities	12,812,000	12,887,000
Total Liabilities	26,448,000	24,161,000
Commitments and Contingencies	0	0
Stockholders' Equity:
Common stock, par value $0.10 per share, authorized 10,000 shares, issued 3,420 shares	342,000	342,000
Additional paid-in capital	53,527,000	52,043,000
Retained earnings	337,700,000	317,745,000
Treasury shares, 1,594 shares in 2020 and 1,565 shares in 2019, at cost	(151,127,000)	(132,260,000)
Total Stockholders' Equity	240,442,000	237,870,000
Total Liabilities and Stockholders' Equity	$ 266,890,000	$ 262,031,000