Quarterly Financial Data

12 Months Ended

Dec. 31, 2013

Quarterly Financial Data - Unaudited [Abstract]

Quarterly Financial Information [Text Block]

Quarterly Financial Data - Unaudited

	Quarter Ended
	March 31		June 30		Sept. 30		Dec. 31
2013
Total revenue	$	74,299	$	78,661	$	82,815	$	77,941
Gross profit	36,794		38,038		40,955		38,945
Net income	8,685		7,367		11,034		13,332
Net income per share:
Basic	$	0.60	$	0.50	$	0.75	$	0.89
Diluted	$	0.58	$	0.48	$	0.72	$	0.86
2012
Total revenue	$	75,511	$	77,281	$	81,405	$	82,672
Gross profit	34,965		39,082		40,695		41,768
Net income	7,601		9,149		12,188		12,343
Net income per share:
Basic	$	0.54	$	0.65	$	0.85	$	0.86
Diluted	$	0.53	$	0.63	$	0.82	$	0.82