CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Income Statement [Abstract]
Net revenues	$ 490,259	$ 356,482	$ 927,183	$ 666,823
Cost of net revenues	124,677	85,565	234,193	160,281
Gross profit	365,582	270,917	692,990	506,542
Operating expenses:
Selling, general and administrative	212,087	162,964	411,712	314,112
Research and development	30,804	24,384	60,395	47,188
Total operating expenses	242,891	187,348	472,107	361,300
Income from operations	122,691	83,569	220,883	145,242
Interest income	1,917	1,441	4,093	2,636
Other income (expense), net	(7,099)	1,771	(6,922)	2,221
Net income before provision for income taxes and equity in losses of investee	117,509	86,781	218,054	150,099
Provision for income taxes	7,703	15,387	10,605	8,164
Equity in losses of investee, net of tax	3,701	2,215	5,478	3,336
Net income	$ 106,105	$ 69,179	$ 201,971	$ 138,599
Net income per share:
Basic (in usd per share)	$ 1.32	$ 0.86	$ 2.52	$ 1.73
Diluted (in usd per share)	$ 1.30	$ 0.85	$ 2.48	$ 1.70
Shares used in computing net income per share:
Basic (in shares)	80,216	80,188	80,127	80,047
Diluted (in shares)	81,471	81,631	81,575	81,668