CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
CONSOLIDATED STATEMENTS OF OPERATIONS [Abstract]
Net sales	$ 3,682,039	$ 3,589,989	$ 3,165,995
Cost of sales	3,151,363	3,100,385	2,712,621
Gross profit	530,676	489,604	453,374
Selling, general and administrative expenses	455,747	416,570	371,995
Special (gains) charges	(5,598)	4,289	7,750
Operating income	80,527	68,745	73,629
Foreign currency exchange loss	1,037	1,750	187
Interest and other income, net	(1,376)	(840)	(1,015)
Interest expense	2,183	1,802	1,372
Income before income taxes	78,683	66,033	73,085
Provision for income taxes	24,275	23,482	26,900
Net income	$ 54,408	$ 42,551	$ 46,185
Net income per common share:
Basic (in dollars per share)	$ 1.48	$ 1.15	$ 1.26
Diluted (in dollars per share)	$ 1.47	$ 1.13	$ 1.24
Weighted average common and common equivalent shares:
Basic (in shares)	36,805	36,996	36,706
Diluted (in shares)	37,096	37,601	37,343
Dividends declared	$ 0	$ 0	$ 0.75