CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 286,219	$ 212,029	$ 208,716
Adjustments to reconcile net income to net cash provided by operating activities:
Amortization of trademark	52	48	68
Depreciation and amortization	17,032	11,728	5,839
(Gain) loss on disposal of property and equipment	(18)	194	(144)
Stock-based compensation	19,424	16,862	14,040
Loss (gain) on put option	727	(3,768)
Loss on investments, net	43	4,526	3,887
Deferred income taxes	(687)	(1,361)	(3,163)
Tax benefit from exercise of stock options	(3,824)	(12,374)	(3,131)
Provision for doubtful accounts	52	1,659	671
Effect on cash of changes in operating assets and liabilities:
Accounts receivable	(56,752)	(12,669)	(77,562)
Distributor receivables	(256)	4,286	86,023
Inventories	(4,465)	(44,973)	8,545
Prepaid expenses and other current assets	(6,209)	(2,774)	(2,872)
Prepaid income taxes	9,470	(9,992)	4,977
Accounts payable	26,250	33,352	(2,185)
Accrued liabilities	8,144	13,174	4,172
Accrued promotional allowances	28,442	14,702	9,712
Accrued distributor terminations	(330)	(2,570)	(99,332)
Accrued compensation	2,878	(66)	838
Income taxes payable	13,918	12,505	3,892
Deferred revenue	(6,283)	(5,474)	(6,799)
Net cash provided by operating activities	333,827	229,044	156,192
CASH FLOWS FROM INVESTING ACTIVITIES:
Maturities of held-to-maturity investments	407,918	107,992	79,919
Sales of available-for-sale investments	30,545	13,201	17,254
Sales of trading investments	34,715	7,400
Purchases of held-to-maturity investments	(583,138)	(257,474)	(74,976)
Purchases of available-for-sale investments	(33,312)	(59,907)
Purchases of property and equipment	(25,552)	(12,545)	(23,554)
Proceeds from sale of property and equipment	519	115	877
Additions to trademarks	(5,132)	(9,852)	(5,215)
Decrease (increase) in other assets	410	(1,440)	1,226
Net cash used in investing activities	(173,027)	(212,510)	(4,469)
CASH FLOWS FROM FINANCING ACTIVITIES:
Principal payments on debt	(1,942)	(420)	(1,539)
Tax benefit from exercise of stock options	3,824	12,374	3,131
Issuance of common stock	20,318	20,824	2,502
Purchases of common stock held in treasury	(176,392)	(23,540)	(86,173)
Net cash (used in) provided by financing activities	(154,192)	9,238	(82,079)
Effect of exchange rate changes on cash and cash equivalents	(2,119)	721	1,904
NET INCREASE IN CASH AND CASH EQUIVALENTS	4,489	26,493	71,548
CASH AND CASH EQUIVALENTS, beginning of year	354,842	328,349	256,801
CASH AND CASH EQUIVALENTS, end of year	359,331	354,842	328,349
Cash paid during the year for:
Interest	48	13	50
Income taxes	$ 147,927	$ 136,369	$ 125,838