Note 7 - Equity-based Compensation (Tables)

12 Months Ended

Dec. 31, 2014

Shareholders' Equity and Share-based Payments [Abstract]

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

A summary of stock award activity during the years ended December 31, 2014, 2013 and 2012 is as follows:

	For the Years Ended December 31,
	2014				2013				2012
	Stock Awards		Weighted Average Award Date Fair Value		Stock Awards		Weighted Average Award Date Fair Value		Stock Awards		Weighted Average Award Date Fair Value
Outstanding, beginning of period	555,025		$	22.79	698,869		$	19.39	643,117		$	17.48
Restricted shares awarded	242,722		23.76		435,025		24.09		239,523		18.07
Restricted stock units awarded	395,352		21.75		112,401		25.11		222,379		18.11
Restricted shares distributed	(118,828	)	23.55		(274,784	)	19.04		(289,001	)	13.42
Restricted stock units distributed	(15,277	)	21.25		(13,761	)	18.87		(15,177	)	14.32
Restricted shares forfeited	(104,013	)	23.77		(236,388	)	23.10		(36,325	)	20.13
Restricted stock units forfeited	(187,441	)	24.48		(166,337	)	19.55		(65,647	)	18.18
Outstanding, end of period	767,540		$	21.93	555,025		$	22.79	698,869		$	19.39

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

The following table summarizes information about deferred stock unit activity during the years ended December 31, 2014, 2013 and 2012:

	For the Years Ended December 31,
	2014				2013				2012
	Deferred Stock Units		Weighted Average Award Date Fair Value		Deferred Stock Units		Weighted Average Award Date Fair Value		Deferred Stock Units		Weighted Average Award Date Fair Value
Outstanding, beginning of period	214,455		$	19.56	181,518		$	19.06	173,916		$	20.12
Awarded	38,810		22.89		39,966		22.33		41,734		17.78
Shares distributed	(31,794	)	19.70		(7,029	)	22.67		(34,132	)	22.90
Outstanding, end of period	221,471		$	20.10	214,455		$	19.56	181,518		$	19.06

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

A summary of stock option activity during the years ended December 31, 2014, 2013 and 2012 is as follows:

	For the Years Ended December 31,
	2014				2013				2012
	Shares		Weighted Average Exercise Price		Shares		Weighted Average Exercise Price		Shares		Weighted Average Exercise Price
Outstanding at January 1	1,208,824		$	18.54	1,216,809		$	18.46	1,107,712		$	18.98
Granted	38,820		24.21		29,025		25.11		281,696		18.11
Exercised	(526,359	)	16.36		(29,511	)	20.14		(52,676	)	16.66
Canceled/Expired	(218,151	)	25.61		(7,499	)	24.58		(119,923	)	23.21
Outstanding at December 31	503,134		$	18.18	1,208,824		$	18.54	1,216,809		$	18.46
Exercisable at December 31	452,236		$	18.12	933,738		$	17.84	758,270		$	16.80

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

Financial data for stock option exercises are summarized in the following table (in thousands):

	Years Ended December 31,
	2014		2013		2012
Amount collected from stock option exercises	$	8,614	$	738	$	1,054
Total intrinsic value of stock option exercises	3,771		131		177
Tax benefit (expense) of stock option exercises recorded in additional paid-in-capital	6		55		66
Aggregate intrinsic value of outstanding stock options	1,231		5,383		5,708
Aggregate intrinsic value of exercisable stock options	1,209		4,695		4,601

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

	2014		2013		2012
	Range	Weighted Average	Range	Weighted Average	Range	Weighted Average
Grant-date fair value	$11.27	$11.27	12.92	$12.92	$8.14-$8.19	$8.19
Volatility	41.6%	41.6%	49.8%	49.8%	43.0%-45.2%	45.1%
Expected term (years)	7.0	7.0	7.0	7.0	7.0	7.0
Dividend yield	—%	—%	—%	—%	—%	—%
Risk-free rate	2.3%	2.3%	1.1%	1.1%	1.0%-1.5%	1.5%