Note 7 - Share-Based Compensation (Tables)

12 Months Ended

Dec. 31, 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				2011
Expected dividend yield at date of grant		2.26	to	3.46%		2.63	to	3.98%		2.00	to	2.55%
Expected stock price volatility		30.34	to	30.51%		29.10	to	31.70%		28.70	to	32.00%
Risk-free interest rate		0.55	to	1.07%		0.56	to	1.15%		1.70	to	2.14%
Expected life of options (in years)		4	to	6		4	to	6		4	to	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		(155,253	)	$	3.36			$	1,126
Forfeited		--			--
Outstanding at December 31, 2013		1,444,845		$	10.21		6.48	$	12,438
Exercisable at December 31, 2013		693,975		$	8.96		5.37	$	6,846
Class B
Outstanding at December 31, 2012		227,959		$	18.45
Granted		38,718		$	29.35
Exercised		(31,875	)	$	14.69			$	992
Forfeited		--			--
Outstanding at December 31, 2013		234,802		$	20.76		6.54	$	3,276
Exercisable at December 31, 2013		109,662		$	18.85		5.43	$	1,739

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 December 31, 2013		60,609	$	5.77		10,101	$	34.65