Note 7 - Share-based Compensation (Tables)

6 Months Ended

Jun. 30, 2017

Notes Tables

Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table Text Block]

	Three Months Ended						Six Months Ended
	June 30,						June 30,
	2017			2016			2017			2016
Share-based compensation expense, gross	$	1,434		$	1,270		$	2,772		$	2,556
Income tax benefit at our statutory rate associated with share-based compensation		(559	)		(495	)		(1,081	)		(997	)
Share-based compensation expense, net	$	875		$	775		$	1,691		$	1,559

Schedule of Nonvested Restricted Stock Units Activity [Table Text Block]

	Six Months Ended
	June 30, 2017					June 30, 2016
				Weighted-					Weighted-
				average					average
				Grant Date					Grant Date
	Number of			Fair Value		Number of			Fair Value
	Shares			Per Share		Shares			Per Share
Restricted stock - common:
Outstanding - beginning of period		396,033		$	12.06		337,506		$	9.57
Granted		307,943		$	10.40		237,500		$	12.88
Vested		(200,291	)	$	11.82		(178,973	)	$	8.46
Outstanding - end of period		503,685		$	11.14		396,033		$	12.06
Restricted stock - Class A common:
Restricted stock - beginning of period		415,082		$	10.15		374,693		$	9.46
Granted		275,076		$	10.84		218,612		$	11.25
Vested		(227,526	)	$	10.00		(178,223	)	$	10.04
Restricted stock - end of period		462,632		$	10.63		415,082		$	10.15