Consolidated Balance Sheets $ in Thousands, CAD in Millions	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Current assets:
Cash and cash equivalents	$ 21,457	$ 24,153
Certificates of deposit	2,880	5,512
Held-to-maturity Securities, Current	6,077	14,083
Accounts receivable, net	50,338	43,001
Income tax receivable	1,643	6,239
Note receivable	28	25
Inventories, net	70,786	47,352
Prepaid expenses and other	518	616
Total current assets	153,727	140,981
Property, plant and equipment:
Land	2,233	2,233
Buildings	92,075	78,806
Machinery and equipment	184,316	158,216
Furniture and fixtures	13,714	12,783
Total property, plant and equipment	292,338	252,038
Less: Accumulated depreciation	149,963	137,146
Property, plant and equipment, net	142,375	114,892
Note receivable, long-term	678	657
Total assets	296,780	256,530
Current liabilities:
Revolving credit facility	0	0
Accounts payable	10,967	7,102
Accrued liabilities	39,098	31,940
Total current liabilities	50,065	39,042
Deferred revenue	1,512	1,498
Deferred tax liabilities	7,977	9,531
Donations	0	561
Commitments and contingencies
Stockholders' equity:
Preferred stock, $.001 par value, 5,000,000 shares authorized, no shares issued
Common stock, $.004 par value, 100,000,000 shares authorized, 52,422,801 and 52,651,448 issued and outstanding at December 31, 2017 and 2016, respectively	210	211
Additional paid-in capital	0	0
Retained earnings	237,016	205,687
Total stockholders' equity	237,226	205,898
Total liabilities and stockholders' equity	$ 296,780	$ 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).

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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.