Condensed Consolidated Statements of Comprehensive Income - USD ($) shares in Thousands, $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Revenues:
Total revenues		$ 1,512,000	$ 1,152,000	$ 4,282,000	$ 3,269,000
Cost of revenues:
Total cost of revenues	[1]	350,000	252,000	979,000	708,000
Gross profit		1,162,000	900,000	3,303,000	2,561,000
Operating expenses:
Sales and marketing	[1]	579,000	454,000	1,660,000	1,321,000
Research and development	[1]	358,000	268,000	1,005,000	740,000
General and administrative	[1]	151,000	109,000	416,000	319,000
Total operating expenses	[1]	1,088,000	831,000	3,081,000	2,380,000
Income from operations		74,000	69,000	222,000	181,000
Interest expense		(7,000)	(8,000)	(21,000)	(25,000)
Other income (expense), net		1,000	(35,000)	16,000	(20,000)
Income before income taxes		68,000	26,000	217,000	136,000
Provision for income taxes		5,000	13,000	13,000	34,000
Net income		$ 62,890	$ 12,858	$ 203,725	$ 101,855
Net income per share - basic (in dollars per share)		$ 0.32	$ 0.07	$ 1.03	$ 0.53
Net income per share - diluted (in dollars per share)		$ 0.31	$ 0.06	$ 1.00	$ 0.50
Weighted-average shares used to compute net income per share - basic (in shares)		198,600	193,237	197,680	193,203
Weighted-average shares used to compute net income per share - diluted (in shares)		203,124	201,861	202,729	202,837
Other comprehensive income:
Foreign currency translation adjustments		$ (20,000)	$ 25,000	$ (37,000)	$ 23,000
Unrealized gain (loss) on investments, net of tax		(2,000)	(3,000)	(9,000)	4,000
Other comprehensive income (loss)		(22,000)	22,000	(46,000)	27,000
Comprehensive income		41,000	35,000	158,000	129,000
Subscription
Revenues:
Total revenues		1,427,000	1,091,000	4,050,000	3,102,000
Cost of revenues:
Total cost of revenues	[1]	264,000	189,000	740,000	521,000
Professional services and other
Revenues:
Total revenues		85,000	61,000	232,000	167,000
Cost of revenues:
Total cost of revenues	[1]	$ 86,000	$ 63,000	$ 239,000	$ 187,000

[1] Includes stock-based compensation as follows:  Three Months Ended September 30,Nine Months Ended September 30,2021202020212020Cost of revenues:Subscription$33 $26 $95 $72 Professional services and other15 13 43 38 Operating expenses:Sales and marketing101 79 293 228 Research and development102 74 288 203 General and administrative40 28 110 84