Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 23,515	$ 24,153
Certificates of deposit	5,040	5,512
Investments held to maturity at amortized cost	11,342	14,083
Accounts receivable, net	57,342	43,001
Income tax receivable	0	6,239
Notes receivable	28	25
Inventories, net	66,117	47,352
Prepaid expenses and other	757	616
Total current assets	164,141	140,981
Property, plant and equipment:
Land	2,233	2,233
Buildings	88,740	78,806
Machinery and equipment	179,712	158,216
Furniture and fixtures	14,136	12,783
Total property, plant and equipment	284,821	252,038
Less: Accumulated depreciation	146,513	137,146
Property, plant and equipment, net	138,308	114,892
Note receivable	689	657
Total assets	303,138	256,530
Current liabilities:
Revolving credit facility	0	0
Accounts payable	18,933	7,102
Dividends payable	0	0
Accrued liabilities	41,682	31,940
Total current liabilities	60,615	39,042
Deferred revenue	1,547	1,498
Deferred tax liabilities	10,678	9,531
Donations	0	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, 52,513,061 and 52,651,448 issued and outstanding at September 30, 2017 and December 31, 2016, respectively	210	211
Additional paid-in capital	0	0
Retained earnings	230,088	205,687
Total stockholders' equity	230,298	205,898
Total liabilities and stockholders' equity	$ 303,138	$ 256,530

Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

Name:	us-gaap_AccountsPayableCurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.