CONSOLIDATED BALANCE SHEET - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Current Assets:
Cash and cash equivalents	$ 58,753	$ 30,136
Short-term investments	9,684	35,468
Accounts receivable, net of allowance for doubtful accounts of $21 and $28 in 2018 and 2017, respectively	17,014	17,076
Inventories	33,572	29,354
Prepaid expenses and other current assets	3,242	3,199
Total Current Assets	122,265	115,233
Long-term investments	21,048	9,136
Property, Plant and Equipment	181,582	167,080
Less accumulated depreciation and amortization	106,689	100,711
Property, Plant and Equipment, net	74,893	66,369
Other Assets and Deferred Charges:
Patents and licenses, net of accumulated amortization of $12,181 and $12,062 in 2018 and 2017, respectively	1,659	1,778
Goodwill	9,730	9,730
Other	1,621	1,534
Prepaid Expense and Other Assets, Noncurrent, Total	13,010	13,042
Total Assets	231,216	203,780
Current Liabilities:
Accounts payable	5,082	3,929
Accrued liabilities	4,519	4,947
Accrued income and other taxes	619	746
Total Current Liabilities	10,220	9,622
Line of credit	0	0
Other Liabilities and Deferred Credits:
Deferred income taxes	6,687	7,312
Other	3,542	2,458
Liabilities Noncurrent	10,229	9,770
Total Liabilities	20,449	19,392
Stockholders' Equity:
Common stock, par value $.10 per share, authorized 10,000 shares, issued 3,420 shares	342	342
Additional paid-in capital	50,391	48,730
Accumulated other comprehensive loss	0	(1,215)
Retained earnings	291,761	268,194
Treasury shares, 1,567 shares in 2018 and 1,568 shares in 2017, at cost	(131,727)	(131,663)
Total Stockholders' Equity	210,767	184,388
Total Liabilities and Stockholders' Equity	$ 231,216	$ 203,780