Note 14 - Stock-based Compensation (Tables)

12 Months Ended

Dec. 31, 2014

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

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

	Year Ended December 31,
	2014			2013			2012
Risk-free interest rate		0.52	%		0.25	%		0.28	%
Expected volatility		17.3	%		31.3	%		38.8	%
Expected life, in years		2.2			2.1			2.1
Expected dividend yield		2.68	%		2.81	%		2.91	%

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

	Number of Shares			Weighted Average Exercise Price		Aggregate Intrinsic Value
Options outstanding at January 1, 2012		1,482,077		$	46.92	$	−
Options granted		63,516			44.28		−
Options exercised		(295,371	)		45.41		−
Options cancelled		(115,620	)		50.99		−
Options outstanding at December 31, 2012		1,134,602			46.75		−
Options granted		57,672			47.95		−
Options exercised		(19,722	)		45.63		−
Options cancelled		(98,000	)		51.11		−
Options outstanding at December 31, 2013		1,074,552			46.44		−
Options granted		57,716			53.10		−
Options exercised		(157,590	)		45.97		−
Options cancelled		(20,000	)		46.69		−
Options outstanding at December 31, 2014		954,678		$	46.92	$	15,202,000
Options exercisable at December 31, 2014		158,573		$	48.06	$	2,344,000

Schedule of Share-based Compensation, Shares Authorized under Stock Option Plans, by Exercise Price Range [Table Text Block]

Options Outstanding December 31, 2014		Exercise Prices	Weighted Average Exercise Price		Weighted Average Remaining Contractual Life in Years
	909,678	$44.80 - $47.45	$	46.62		1.3
	45,000	$52.93	$	52.93		4.3
	954,678		$	46.92		1.5

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

	Number of Shares		Weighted Average Grant Date Fair Value		Aggregate Intrinsic Value
Unvested restricted shares at January 1, 2012		24,000	$	34.46	$	−
Award shares granted		−		−		−
Award shares vested		6,000		34.46		−
Unvested restricted shares at December 31, 2012		18,000		34.46		−
Award shares granted		−		−		−
Award shares vested		6,000		34.46		−
Unvested restricted shares at December 31, 2013		12,000		34.46		−
Award shares granted		−		−		−
Award shares vested		6,000		34.46		−
Unvested restricted shares at December 31, 2014		6,000	$	34.46	$	170,000