Note 3 - Stock-Based Compensation (Detail) - Summary of stock option activity: (USD $)	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012
Weighted Average Exercise Price (in Dollars per share)	$ 4.53	$ 4.40
# of shares	121,600	115,600
Weighted Average Exercise Price (in Dollars per share)	$ 6.87	$ 5.27
# of shares	12,000	12,000
Weighted Average Exercise Price (in Dollars per share)	$ 4.74	$ 4.48
# of shares	133,600	127,600
Weighted Average Remaining Contractual Term (in years)	4 years 354 days	5 years 138 days
Aggregate Intrinsic Value (in Dollars)	$ 218,446	$ 216,332
Weighted Average Exercise Price (in Dollars per share)	$ 4.53	$ 4.40
# of shares	121,600	115,600
Weighted Average Remaining Contractual Term (in years)	4 years 302 days	4 years 328 days
Aggregate Intrinsic Value (in Dollars)	$ 206,760	$ 206,332

Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Gross number of share options (or share units) granted during the period.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of options outstanding.

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The number of shares reserved for issuance under stock option agreements awarded under the plan that validly exist and are outstanding as of the balance sheet date, including vested options.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average price at which grantees can acquire the shares reserved for issuance on stock options awarded.

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