CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands	6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010
CASH FLOWS FROM OPERATING ACTIVITIES
Net earnings	$ 1,643	$ 926
Adjustments to reconcile net earnings to net cash provided by operating activities:
Depreciation and amortization	3,592	3,623
Deferred income taxes	(105)	(347)
Provision for allowances	383	597
Share-based compensation	361	261
Change in fair value of interest rate swaps	(60)	132
Decommissioning retirement liability	29	26
Loss on sale of equipment	2	39
Changes in assets and liabilities:
Accounts receivable	(1,495)	(2,321)
Inventories	(1,550)	(1,576)
Prepaid expenses and other current assets	(53)	(2)
Trade accounts payable	96	922
Accrued salaries, wages and payroll taxes	341	(9)
Income taxes payable	462	597
Other current liabilities	(195)	327
Other	(56)	(149)
Net cash provided by operating activities	3,395	3,046
CASH FLOWS FROM INVESTING ACTIVITIES
Purchases and construction of property and equipment	(1,304)	(7,044)
Proceeds from sale of property and equipment	5	6
Purchases of marketable securities	(7,743)	(12,585)
Maturities of marketable securities	5,955	1,160
Proceeds from sales of marketable securities		200
Net cash used by investing activities	(3,087)	(18,263)
CASH FLOWS FROM FINANCING ACTIVITIES
Repayment of borrowings	(1,667)	(1,667)
Employee stock purchase plan	27
Retirement of common stock	(14)
Net cash used by financing activities	(1,654)	(1,667)
NET DECREASE IN CASH AND CASH EQUIVALENTS	(1,346)	(16,884)
CASH AND CASH EQUIVALENTS AT BEGINNING OF PERIOD	29,674	45,326
CASH AND CASH EQUIVALENTS AT END OF PERIOD	28,328	28,442
SUPPLEMENTARY CASH FLOW DISCLOSURE:
Interest paid	417	471
Income taxes paid	613	480
NON-CASH INVESTING AND FINANCING ACTIVITIES:
Liability for property and equipment acquired	$ 63	$ 669