Consolidated Statements of Income (Unaudited) (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
Consolidated Statements of Income (Unaudited) [Abstract]
Revenue	$ 593,235	$ 424,426	$ 1,055,237	$ 820,271
Cost of sales	95,584	71,168	171,340	171,822	[1]
Gross profit	497,651	353,258	883,897	648,449
Operating expenses:
Selling expenses	267,363	183,500	469,898	352,642
General and administrative expenses	132,376	103,712	244,424	204,854
Total operating expenses	399,739	287,212	714,322	557,496
Operating income	97,912	66,046	169,575	90,953
Other income (expense), net	(3,369)	(127)	266	(549)
Income before provision for income taxes	94,543	65,919	169,841	90,404
Provision for income taxes	34,136	24,218	61,605	33,395
Net income	$ 60,407	$ 41,701	$ 108,236	$ 57,009
Net income per share (Note 2):
Basic (in dollars per share)	$ 0.98	$ 0.67	$ 1.75	$ 0.92
Diluted (in dollars per share)	$ 0.94	$ 0.65	$ 1.67	$ 0.89
Weighted-average common shares outstanding (000s):
Basic (in shares)	61,706	61,806	62,016	61,817
Diluted (in shares)	64,230	64,193	64,773	64,177

[1] Includes a $32.8 million non-cash charge related to an adverse decision in the Japan customs litigation. See Note 12.