Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Income Statement [Abstract]
Revenue	$ 842,708	$ 764,302
Costs and operating expenses:
Cost of revenue (exclusive of amortization of acquired intangible assets shown below)	306,687	268,582
Research and development	82,045	71,224
Sales and marketing	116,354	123,786
General and administrative	136,715	127,361
Amortization of acquired intangible assets	11,427	10,434
Restructuring charge	7,116	10,585
Total costs and operating expenses	660,344	611,972
Income from operations	182,364	152,330
Interest income	4,578	7,043
Interest expense	(17,834)	(17,205)
Other expense, net	(817)	(4,108)
Income before provision for income taxes	168,291	138,060
Provision for income taxes	(11,898)	(14,292)
Loss from equity method investment	(698)	(622)
Net income	$ 155,695	$ 123,146
Net income per share:
Basic (in dollars per share)	$ 0.95	$ 0.76
Diluted (in dollars per share)	$ 0.94	$ 0.75
Shares used in per share calculations:
Basic (in shares)	163,061	161,992
Diluted (in shares)	165,688	163,684