Note 12 - Selected Quarterly Financial Data (Unaudited) (Tables)

12 Months Ended

Dec. 31, 2012

Schedule of Quarterly Financial Information [Table Text Block]

	First Quarter		Second Quarter		Third Quarter		Fourth Quarter
Year ended December 31, 2012:
Revenues	$	230,594	$	257,531	$	265,155	$	274,683
Gross profit		52,684		62,427		62,774		65,224
Operating income		10,899		18,363		26,142		23,718
Net income		6,724		11,498		19,544		14,895
Basic earnings per share:
Net income	$	0.17	$	0.29	$	0.50	$	0.38
Diluted earnings per share
Net income	$	0.17	$	0.29	$	0.49	$	0.38

Year ended December 31, 2011:
Revenues	$	210,587	$	224,985	$	246,218	$	256,795
Gross profit		41,174		45,840		52,629		63,481
Operating income		5,489		7,840		9,498		21,710
Net income		3,006		7,629		1,160		14,752
Basic earnings per share:
Net income	$	0.08	$	0.19	$	0.03	$	0.37
Diluted earnings per share
Net income	$	0.08	$	0.19	$	0.03	$	0.37