Note 10 - Stock-Based Compensation (Tables)

6 Months Ended

Jun. 30, 2014

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Schedule of Compensation Cost for Share-based Payment Arrangements, Allocation of Share-based Compensation Costs by Plan [Table Text Block]

	Three Months Ended June 30,						Six Months Ended June 30,
	2014			2013			2014			2013
Total cost of stock-based compensation	$	141,570		$	128,567		$	284,177		$	260,675
Amount of income tax benefit recognized in earnings		(21,790	)		(21,799	)		(42,964	)		(43,803	)
Amount charged against net income	$	119,780		$	106,768		$	241,213		$	216,872

Schedule of Share-based Compensation, Stock Options, Activity [Table Text Block]

	Number of Shares			Weighted Average Exercise Price per Share		Weighted Average Remaining Contractual Term		Aggregate Intrinsic Value
Outstanding at December 31, 2013		622,300		$	12.34		3.7	$	2,174,673
Options granted		146,400		$	15.86		6.5
Options cancelled/expired		(3,800	)	$	15.46		--
Options exercised		(54,100	)	$	9.94		--
Outstanding at June 30, 2014		710,800		$	13.23		4.0	$	1,860,165
Exercisable at June 30, 2014		523,406		$	12.46		3.4	$	1,771,538

Schedule of Share-based Compensation Stock Options Unvested Activity [Table Text Block]

	Number of Shares			Weighted Average Grant Date Fair Value
Unvested at December 31, 2013		79,225		$	3.98
Options granted		146,400		$	4.13
Options cancelled		(3,225	)	$	3.89
Options vested		(35,006	)	$	4.39
Unvested at June 30, 2014		187,394		$	4.02