Note 11 - Stock Option and Equity Incentive Plans (Tables)

12 Months Ended

Dec. 31, 2016

Notes Tables

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

	Shares Under Options			Weighted Average Exercise Price  (per share)		Weighted Average Remaining Contractual Life (in years)		Aggregate Intrinsic Value (in thousands)
Outstanding December 31, 2015		270,205		$	15.40
Granted		17,184			22.02
Exercised		(54,811	)		24.57
Outstanding December 31, 2016		232,578		$	16.53		3.66	$	2,074
Exercisable at December 31, 2016		210,078		$	16.02		3.86	$	1,981
Vested and expected to vest at December 31, 2016		232,578		$	16.53		3.66	$	2,074

Schedule of Share-based Compensation, Restricted Stock Units Award Activity [Table Text Block]

	Restricted Stock Units			Weighted Average Award Date Fair Value
Outstanding at December 31, 2015		40,645		$	19.67
Awarded		17,822			21.66
Shares vested		(11,909	)		20.94
Outstanding at December 31, 2016		46,558		$	20.05

Schedule of Future Share-based Compensation Expense [Table Text Block]

	Options		Common Stock		Restricted Stock Units		Total
2017		44		-		293		337
2018		16		-		207		223
2019		-		-		110		110
2020		-		-		23		23
Total	$	60	$	-	$	633	$	693