Note 5 - Share-Based Compensation (Tables)

9 Months Ended

Sep. 30, 2013

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

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]

	2013			2012
Expected dividend yield at date of grant	2.26	-	3.46%	2.63	-	3.98%
Expected stock price volatility	30.34	-	30.51%	29.10	-	31.70%
Risk-free interest rate	0.55	-	1.07%	0.56	-	1.15%
Expected life of options (in years)	4	-	6	4	-	6

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

	Number of Options			Weighted  Average Exercise Price		Weighted Average Remaining Contractual Terms (Years)		Aggregate Intrinsic Value (In thousands)
Class A
Outstanding at December 31, 2012		1,367,754		$	8.45
Granted		232,344		$	15.98
Exercised		(119,253	)	$	2.20
Forfeited		-			-
Outstanding at September 30, 2013		1,480,845		$	10.14		6.66	$	12,872
Exercisable at September 30, 2013		729,975		$	8.87		5.53	$	7,271
Class B
Outstanding at December 31, 2012		227,959		$	18.45
Granted		38,718		$	29.35
Exercised		(19,875	)	$	13.20
Forfeited		-			-
Outstanding at September 30, 2013		246,802		$	20.58		6.66	$	2,310
Exercisable at September 30, 2013		121,662		$	18.68		5.53	$	1,360

Schedule of Nonvested Share Activity [Table Text Block]

	Class A Shares Outstanding		Class A Weighted Average Grant Date Fair Value Per Share		Class B Shares Outstanding		Class B Weighted Average Grant Date Fair Value Per Share
Outstanding at December 31, 2012		60,609	$	5.77		10,101	$	34.65
Granted		-		-		-		-
Vested		-		-		-		-
Forfeited		-		-		-		-
Outstanding at September 30, 2013		60,609	$	5.77		10,101	$	34.65