Condensed Consolidated Statements Of Income (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Consolidated Statements Of Operations [Abstract]
Revenues	$ 288,524	$ 295,569	$ 964,007	$ 898,309
Cost of sales	134,943	134,826	443,710	396,682
Gross profit	153,581	160,743	520,297	501,627
Selling, general and administrative expenses	135,674	120,729	414,119	349,737
Asset impairment			202	819
Income from operations	17,907	40,014	105,976	151,071
Foreign currency transaction losses, net	1,043	21	4,457	2,670
Interest income	(853)	(151)	(1,676)	(1,057)
Interest expense	44	377	519	556
Other (income) expense, net	13	71	180	(690)
Income before taxes	17,660	39,696	102,496	149,592
Income tax expense (benefit)	4,624	(5,384)	25,143	14,642
Net income	$ 13,036	$ 45,080	$ 77,353	$ 134,950
Net income per common share (Note 11):
Basic	$ 0.15	$ 0.50	$ 0.88	$ 1.50
Diluted	$ 0.15	$ 0.49	$ 0.87	$ 1.48