Condensed Consolidated Statements of Comprehensive Income - USD ($) shares in Thousands, $ in Thousands		3 Months Ended		9 Months Ended
		Oct. 31, 2020	Oct. 31, 2019	Oct. 31, 2020	Oct. 31, 2019
Revenues:
Total revenues		$ 377,519	$ 280,921	$ 1,068,308	$ 792,573
Cost of revenues:
Total cost of revenues	[1]	102,997	73,329	295,081	209,050
Gross profit		274,522	207,592	773,227	583,523
Operating expenses:
Research and development	[1]	79,992	52,575	212,282	148,694
Sales and marketing	[1]	57,982	45,524	172,909	130,962
General and administrative	[1]	35,243	28,693	109,085	78,042
Total operating expenses	[1]	173,217	126,792	494,276	357,698
Operating income		101,305	80,800	278,951	225,825
Other income, net		3,455	9,141	9,750	22,634
Income before income taxes		104,760	89,941	288,701	248,459
Provision for income taxes		7,801	7,696	11,621	13,523
Net income		96,959	82,245	277,080	234,936
Net income, basic and diluted		$ 96,959	$ 82,245	$ 277,080	$ 234,936
Net income per share:
Basic (in usd per share)		$ 0.64	$ 0.56	$ 1.84	$ 1.59
Diluted (in usd per share)		$ 0.60	$ 0.52	$ 1.73	$ 1.49
Weighted-average shares used to compute net income per share:
Basic (in shares)		150,993	148,157	150,322	147,467
Diluted (in shares)		161,711	158,750	160,517	158,124
Other comprehensive income:
Net change in unrealized gain on available-for-sale investments		$ (1,230)	$ 753	$ 1,198	$ 2,176
Net change in cumulative foreign currency translation loss		(1,438)	(487)	1,844	(2,931)
Comprehensive income		94,291	82,511	280,122	234,181
Subscription services
Revenues:
Total revenues		302,938	226,760	856,675	642,187
Cost of revenues:
Total cost of revenues	[1]	45,845	31,964	132,457	93,822
Professional services and other
Revenues:
Total revenues		74,581	54,161	211,633	150,386
Cost of revenues:
Total cost of revenues	[1]	$ 57,152	$ 41,365	$ 162,624	$ 115,228

[1] (1) Includes stock-based compensation as follows:Cost of revenues:Cost of subscription services$1,149 $560 $3,700 $1,528 Cost of professional services and other7,510 4,825 19,902 12,261 Research and development17,685 9,899 45,523 25,732 Sales and marketing10,711 6,882 30,089 19,207 General and administrative11,918 7,155 36,032 19,719 Total stock-based compensation$48,973 $29,321 $135,246 $78,447