CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Income Statement [Abstract]
Net revenues	$ 607,341	$ 505,289	$ 1,757,009	$ 1,432,472
Cost of net revenues	169,787	133,508	485,070	367,701
Gross profit	437,554	371,781	1,271,939	1,064,771
Operating expenses:
Selling, general and administrative	277,514	213,873	792,572	625,585
Research and development	39,680	32,700	116,034	93,095
Impairments and other (gains) charges	(6,792)	0	22,990	0
Litigation settlement gain	0	0	(51,000)	0
Total operating expenses	310,402	246,573	880,596	718,680
Income from operations	127,152	125,208	391,343	346,091
Interest income	3,478	2,234	9,576	6,327
Other income (expense), net	(2,211)	(837)	5,935	(7,759)
Net income before provision for income taxes and equity in losses of investee	128,419	126,605	406,854	344,659
Provision for income taxes	25,895	24,601	77,812	35,206
Equity in losses of investee, net of tax	0	1,132	7,528	6,610
Net income	$ 102,524	$ 100,872	$ 321,514	$ 302,843
Net income per share:
Basic (in usd per share)	$ 1.29	$ 1.26	$ 4.03	$ 3.78
Diluted (in usd per share)	$ 1.28	$ 1.24	$ 4.00	$ 3.71
Shares used in computing net income per share:
Basic (in shares)	79,332	80,111	79,709	80,122
Diluted (in shares)	79,825	81,359	80,397	81,538