Quarterly Results Quarterly Results (Tables)

12 Months Ended

Dec. 31, 2013

Quarterly Results [Abstract]

Schedule of Quarterly Financial Information [Table Text Block]

Quarterly results (unaudited)

(in thousands, except per share data)	December 31, 2013		September 30, 2013		June 30, 2013			March 31, 2013
Total revenue	$	134,872	$	127,854	$	125,468		$	115,623
Gross profit	68,514		71,740		68,855			62,045
Income from operations	14,622		18,008		14,318			4,594
Income before provision for income taxes	13,287		16,490		12,532			3,020
Net income	11,790		9,393		6,623			2,666
Earnings per share
Basic	$	0.26	$	0.21	$	0.15		$	0.06
Diluted	$	0.26	$	0.21	$	0.15		$	0.06
(in thousands, except per share data)	December 31, 2012		September 30, 2012		June 30, 2012			March 31, 2012
Total revenue	$	120,051	$	122,472	$	110,190		$	94,706
Gross profit	64,299		67,344		59,685			53,631
Income (loss) from operations	9,875		6,185		(1,877		)	5,252
Income (loss) before provision for income taxes	7,342		4,629		(3,446		)	4,800
Net income (loss)	3,270		2,825		(2,271		)	2,759
Earnings (loss) per share
Basic	$	0.07	$	0.06	$	(0.05	)	$	0.06
Diluted	$	0.07	$	0.06	$	(0.05	)	$	0.06