Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Jul. 31, 2012	Jul. 31, 2011	Jul. 31, 2010
Cash Flows from Operating Activities
Net income	$ 5,586	$ 5,633	$ 5,733
Plus: Loss from discontinued operations - net of tax	382	36	34
Income from continuing operations	5,968	5,669	5,767
Adjustments to reconcile net income to net cash provided by operating activities
Depreciation	1,093	972	986
Amortization	600	653	879
Provision for doubtful accounts receivable	50	(9)	(48)
Stock-based compensation	764	358	287
Deferred income taxes	153	(6,388)	(588)
Loss (gain) on sale of equipment	0	50	(16)
Loss (gain) on sale of product line	0	99	(817)
(Increases) decreases in:
Accounts receivable	(843)	(2,095)	(303)
Inventories	(3,695)	(291)	3,138
Prepaid expenses	93	(150)	(389)
Income taxes refundable	219	0	0
Increase in:
Accounts payable	615	(253)	(112)
Accrued expenses	(183)	427	(453)
Deferred revenue	(1,494)	(430)	19,030
Income taxes payable	(5,848)	6,243	(9)
Net cash (used in) provided by operating activities	(2,508)	4,855	27,352
Net cash provided by (used in) discontinued operations	59	(68)	(43)
Net cash (used in) provided by operating activities	(2,449)	4,787	27,309
Cash Flows from Investing Activities
Proceeds on the sale of equipment	0	11	16
Purchase of property and equipment	(1,809)	(1,687)	(892)
Acquisition of patents and other intangibles	(214)	(273)	(64)
Proceeds from the sale of product line	0	0	1,527
Increase in cash value of life insurance	(11)	(10)	(9)
Net cash (used in) provided by continuing investing activities	(2,034)	(1,959)	578
Net cash (used in) discontinued operations	0	(382)	(241)
Net cash provided (used) in investing activities	(2,034)	(2,341)	337
Cash Flows from Financing Activities
Excess of outstanding checks over bank balance	0	0	(75)
Net borrowings (repayments) on lines-of-credit	0	0	(5,035)
Principal payments on revenue bonds payable	0	(1,728)	(1,935)
Payment on debt incurred for acquisition of trademark	(313)	(598)	(564)
Principal payments on long-term debt	(740)	(685)	(1,620)
Tax benefit associated with the exercise of non-qualified stock options	24	125	31
Proceeds from the issuance of common stock	35	210	68
Net cash (used in) financing activities	(994)	(2,676)	(9,130)
Foreign exchange rate effect on cash and cash equivalents	(242)	(40)	(7)
Net (decrease) increase in cash and cash equivalents	(5,719)	(270)	18,509
Cash and cash equivalents
Beginning	18,399	18,669	160
Ending	12,680	18,399	18,669
Cash paid for:
Interest	63	223	510
Income taxes paid	7,950	2,488	3,692
Supplemental Schedule of Non-cash Investing and Financing Activity
Purchase of equipment included in accounts payable	$ 0	$ 14	$ 65