Consolidated Statements of Income (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Consolidated Statements of Income (Unaudited) [Abstract]
Revenue	$ 471,831	$ 543,332
Cost of sales	137,869	105,055
Gross profit	333,962	438,277
Operating expenses:
Selling expenses	195,559	234,005
General and administrative expenses	130,254	135,626
Total operating expenses	325,813	369,631
Operating income	8,149	68,646
Other income (expense), net	(2,863)	(12,268)
Income before provision for income taxes	5,286	56,378
Provision for income taxes	1,970	20,096
Net income	$ 3,316	$ 36,282
Net income per share (Note 2):
Basic (in dollars per share)	$ 0.06	$ 0.62
Diluted (in dollars per share)	$ 0.06	$ 0.60
Weighted-average common shares outstanding (000s):
Basic (in shares)	55,955	58,991
Diluted (in shares)	56,411	60,261