Note 13 - Stock-based Compensation (Tables)

9 Months Ended

Sep. 30, 2017

Notes Tables

Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table Text Block]

	For three months ended						For nine months ended
	September 30,						September 30,
(in thousands)	2017			2016			2017			2016
Stock-based compensation expense before income taxes	$	670		$	573		$	2,012		$	1,646
Less: deferred tax benefit		(235	)		(200	)		(704	)		(576	)
Reduction of net income	$	435		$	373		$	1,308		$	1,070

Schedule of Share-based Compensation Arrangement by Share-based Payment Award Fair Value Assumptions and Methodology [Table Text Block]

	2017			2016
Dividend yield		2.72	%		2.94	%
Expected volatility		19.47	%		19.31	%
Risk free interest rate		2.29	%		1.70	%
Expected life of SARs (in years)		7.0			7.3

Schedule of Share-based Compensation, Stock Options and Stock Appreciation Rights Award Activity [Table Text Block]

														Weighted
								Weighted		Aggregate		Weighted		average
	Options							average		intrinsic		average		remaining
	and SARs			Exercise				exercise		value		fair		contractual
	(in thousands)			price				price		(in thousands)		value		life (in years)
At December 31, 2015
Vested and exercisable		656		$	14.02	-	19.44	$	15.75	$	6,191	$	3.39		3.7
Unvested		266			15.24	-	24.55		18.66		1,733		3.29		7.7
Total outstanding		922			14.02	-	24.55		16.59		7,924		3.36		4.8
Granted		88			25.76	-	33.08		25.84		1,866		3.56
Exercised		(272	)		14.02	-	17.89		16.38		4,155		3.73
Forfeited		(3	)		14.02	-	15.84		15.18		60		2.94
At December 31, 2016
Vested and exercisable		475			14.02	-	24.56		15.72		14,820		3.16		4.3
Unvested		260			15.24	-	33.08		21.53		6,623		3.43		7.8
Total outstanding		735			14.02	-	33.08		17.78		21,443		3.26		5.5
Granted		46			40.00	-	40.00		40.00		-		6.34
Exercised		(47	)		14.02	-	17.89		15.52		1,168		3.27
Forfeited		-				-			-		-		-
At September 30, 2017
Vested and exercisable		519			14.02	-	25.76		16.39		11,218		3.15		4.3
Unvested		215			15.24	-	40.00		26.45		2,567		4.17		7.9
Total outstanding		734			14.02	-	40.00		19.17	$	13,785		3.45		5.3
Vested year-to-date		92		$	15.24	-	25.76	$	19.34	$	1,723	$	3.18

Schedule of Nonvested Share Activity [Table Text Block]

				Grant date
				weighted-
	Number			average cost
Unvested at December 31, 201 5		155,858		$	18.98
2016 activity:
Shares awarded		51,122			25.78
Restrictions lapsed and shares released		(49,265	)		17.98
Shares forfeited		(12,480	)		20.69
Unvested at December 31, 2016		145,235		$	21.57
2017 activity:
Shares awarded		28,625			44.85
Restrictions lapsed and shares released		(46,220	)		19.76
Shares forfeited		(7,154	)		25.03
Unvested at September 30, 2017		120,486		$	27.59

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

	Vesting				Expected
Grant	period		Fair		shares to
year	in years		value		be awarded
2015		3	$	20.02		51,910
2016		3		22.61		58,786
2017		3		35.66		24,756