Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 7,265	$ 21,457
Certificates of deposit	2,160	2,880
Investments held to maturity at amortized cost	1,252	6,077
Accounts receivable, net	51,207	50,338
Income tax receivable	2,292	1,643
Notes receivable	28	28
Inventories, net	79,182	70,786
Prepaid expenses and other	1,310	518
Total current assets	144,696	153,727
Property, plant and equipment:
Land	3,029	2,233
Buildings	97,944	92,075
Machinery and equipment	210,182	184,316
Furniture and fixtures	16,035	13,714
Total property, plant and equipment	327,190	292,338
Less: Accumulated depreciation	162,294	149,963
Property, plant and equipment, net	164,896	142,375
Intangible assets, net	564	0
Goodwill	3,229	0
Note receivable	639	678
Total assets	314,024	296,780
Current liabilities:
Revolving credit facility	0	0
Accounts payable	16,224	10,967
Accrued liabilities	37,492	39,098
Total current liabilities	53,716	50,065
Deferred revenue	1,638	1,512
Deferred tax liabilities	8,841	7,977
Donations	200	0
Commitments and contingencies
Stockholders' equity:
Preferred stock, $.001 par value, 5,000,000 shares authorized, no shares issued	0	0
Common stock, $.004 par value, 100,000,000 shares authorized, 52,209,643 and 52,422,801 issued and outstanding at September 30, 2018 and December 31, 2017, respectively	209	210
Additional paid-in capital	0	0
Retained earnings	249,420	237,016
Total stockholders' equity	249,629	237,226
Total liabilities and stockholders' equity	$ 314,024	$ 296,780