UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF INCOME AND COMPREHENSIVE INCOME (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF INCOME AND COMPREHENSIVE INCOME [Abstract]
Sales	$ 261,894	$ 197,675	$ 514,181	$ 380,762
Cost of sales	185,265	140,410	366,078	271,070
Gross profit	76,629	57,265	148,103	109,692
Selling, general and administrative expense	55,782	43,634	107,351	84,519
Operating income	20,847	13,631	40,752	25,173
Other income	(3)	15	12	36
Interest expense	(762)	(1,023)	(1,591)	(2,045)
Income before income taxes	20,082	12,623	39,173	23,164
Provision for income taxes	7,905	5,013	15,350	9,211
Net income	12,177	7,610	23,823	13,953
Preferred stock dividend	(22)	(22)	(45)	(45)
Net income attributable to common shareholders	12,155	7,588	23,778	13,908
Net income	12,177	7,610	23,823	13,953
Loss on long-term investment, net of income taxes	(52)	0	(281)	0
Loss on foreign currency valuation, net of income taxes	(117)	0	(117)	0
Comprehensive income	$ 12,008	$ 7,610	$ 23,425	$ 13,953
Basic income per share (in dollars per share)	$ 0.84	$ 0.53	$ 1.66	$ 0.97
Weighted average common shares outstanding (in shares)	14,392	14,327	14,360	14,303
Diluted income per share (in dollars per share)	$ 0.80	$ 0.50	$ 1.57	$ 0.92
Weighted average common and common equivalent shares outstanding (in shares)	15,232	15,167	15,200	15,143