Note D - Income Taxes (Detail) - Reconciliation of the Company's effective income tax rate (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Income taxes at statutory federal income tax rate of 34%	$ 2,355,000	$ 2,337,000
Income taxes at statutory federal income tax rate of 34%	34.00%	34.00%
State income taxes, net of Federal benefit	14,000	14,000
State income taxes, net of Federal benefit	0.20%
Domestic Production Activities tax benefit	(167,000)	(164,000)
Domestic Production Activities tax benefit	(2.40%)	(2.00%)
Nondeductible expenses	1,000	1,000
Prior year over-accrual	(24,000)	(9,000)
Prior year over-accrual	(0.40%)
R&D credits	(83,000)	(20,000)
R&D credits	(12.10%)
Other, misc	1,000
Tax exempt income	(1,000)	(4,000)
Actual income tax expense	$ 2,096,000	$ 2,155,000
Actual income tax expense	30.00%	32.00%