Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 33,552	$ 24,153
Certificates of deposit	5,520	5,512
Investments held to maturity at amortized cost	12,732	14,083
Accounts receivable, net	43,114	43,001
Income tax receivable	809	6,239
Notes receivable	26	25
Inventories, net	63,075	47,352
Prepaid expenses and other	888	616
Total current assets	159,716	140,981
Property, plant and equipment:
Land	2,233	2,233
Buildings	83,401	78,806
Machinery and equipment	168,375	158,216
Furniture and fixtures	13,458	12,783
Total property, plant and equipment	267,467	252,038
Less: Accumulated depreciation	142,839	137,146
Property, plant and equipment, net	124,628	114,892
Note receivable	667	657
Total assets	285,011	256,530
Current liabilities:
Revolving credit facility	0	0
Accounts payable	14,108	7,102
Dividends payable	6,849	0
Accrued liabilities	34,293	31,940
Total current liabilities	55,250	39,042
Deferred revenue	1,542	1,498
Deferred tax liabilities	9,895	9,531
Donations	577	561
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, 52,615,921 and 52,651,448 issued and outstanding at June 30, 2017 and December 31, 2016, respectively	210	211
Additional paid-in capital	0	0
Retained earnings	217,537	205,687
Total stockholders' equity	217,747	205,898
Total liabilities and stockholders' equity	$ 285,011	$ 256,530