Consolidated Balance Sheets (USD $)	Dec. 31, 2012	Dec. 31, 2011
Current assets:
Cash and cash equivalents	$ 2,415,416	$ 8,425,846
Marketable securities, current	5,495,556	4,304,912
Trade accounts receivable, less allowance for doubtful accounts of $303,839 in 2012 and $150,921 in 2011	10,407,649	4,675,464
Other receivables	244,081	101,951
Inventories	6,344,982	4,479,929
Prepaid income taxes	279,964	9,239
Prepaid expenses, other	799,124	511,299
Deferred income taxes	926,081	848,597
Total current assets	26,912,853	23,357,237
Marketable securities, noncurrent	210,440	5,799,417
Property, plant, and equipment, net	5,350,310	3,174,748
Goodwill	8,729,438	3,119,246
Investment in affiliated company	3,303,750	3,237,250
Intangible assets, net	12,381,614	909,536
Other assets	308,996	86,717
Deferred income taxes	22,370	20,360
Total assets	57,219,771	39,704,511
Current liabilities:
Current maturities of long-term notes payable	2,566,154
Revolving lines of credit	5,327,515
Accounts payable	2,893,225	1,812,779
Compensation and related expenses	3,510,272	2,313,553
Other accrued expenses	868,199	406,378
Accrued product warranties	240,621	205,506
Accrued income taxes	36,139
Dividends payable	579,386	543,881
Deferred revenue	472,185	857,906
Total current liabilities	16,493,696	6,140,003
Notes payable	3,926,863
Obligations to former employees	76,161	46,751
Deferred income taxes	2,576,396
Accrued income taxes	265,207	277,978
Total noncurrent liabilities	6,844,627	324,729
Total liabilities	23,338,323	6,464,732
Commitments and contingencies (Note 8)
Stockholders' equity:
Capital stock-undesignated. Authorized 3,000,000 shares; none issued and outstanding in 2012 and 2011
Common stock-$0.10 par value. Authorized 22,000,000 shares; issued and outstanding 5,517,966 shares in 2012 and 5,438,810 shares in 2011	551,797	543,881
Additional paid-in capital	3,738,968	2,762,524
Retained earnings	30,217,977	30,523,405
Accumulated other comprehensive loss	(627,294)	(590,031)
Total stockholders' equity	33,881,448	33,239,779
Total liabilities and stockholders' equity	$ 57,219,771	$ 39,704,511