Note 6 - Share-based Compensation (Tables)

9 Months Ended

Sep. 30, 2015

Notes Tables

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

	2015								2014
	Class A				Class B				Class A				Class B
Expected dividend yield at date of grant		2.14	to	2.57%		5.29	to	5.72%		1.47	to	1.97%		4.03	to	4.87%
Expected stock price volatility		30.86	to	34.87%		29.96	to	33.94%		27.52	to	32.03%		30.13	to	32.65%
Risk-free interest rate		1.55	to	1.78%		1.55	to	1.78%		1.63	to	2.37%		1.63	to	2.37%
Expected life of options (in years)		5	to	7		5	to	7		5	to	7		5	to	7

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, 2014		1,324,520		$	11.07
Granted		225,306		$	13.83
Exercised		(25,983	)	$	6.30			$	179
Forfeited		(56,105	)	$	13.12
Outstanding at September 30, 2015		1,467,738		$	11.50		6.10	$	2,774
Exercisable at September 30, 2015		1,059,990		$	11.04		5.41	$	2,478
Class B
Outstanding at December 31, 2014		213,470		$	24.32
Granted		37,551		$	34.85
Exercised		(4,330	)	$	14.82			$	89
Forfeited		(9,018	)	$	27.61
Outstanding at September 30, 2015		237,673		$	26.04		6.16	$	2,047
Exercisable at September 30, 2015		170,663		$	24.94		5.47	$	1,703

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, 2014		110,647		$	11.10		18,441		$	36.42
Granted		52,660		$	13.17		8,776		$	35.48
Vested		--			--		--			--
Forfeited		(16,249	)	$	5.39		(2,708	)	$	32.31
Outstanding at September 30, 2015		147,058		$	12.47		24,509		$	36.54