Condensed Consolidated Statements of Comprehensive Income - USD ($) shares in Thousands, $ in Thousands		3 Months Ended
		Apr. 30, 2019	Apr. 30, 2018
Revenues:
Revenues		$ 244,752	$ 195,547
Cost of revenues:
Cost of revenues	[1]	65,503	60,155
Gross profit		179,249	135,392
Operating expenses:
Research and development	[1]	44,973	37,197
Sales and marketing	[1]	39,617	34,385
General and administrative	[1]	23,490	19,854
Total operating expenses	[1]	108,080	91,436
Operating income		71,169	43,956
Other income, net		6,161	2,139
Income before income taxes		77,330	46,095
Provision for income taxes		3,881	1,785
Net income		73,449	44,310
Net income attributable to Class A and Class B common stockholders, basic and diluted		$ 73,449	$ 44,310
Net income per share attributable to Class A and Class B common stockholders:
Basic		$ 0.50	$ 0.31
Diluted		$ 0.47	$ 0.29
Weighted-average shares used to compute net income per share attributable to Class A and Class B common stockholders:
Basic		146,708	142,777
Diluted		157,910	154,935
Other comprehensive income:
Net change in unrealized gain on available-for-sale investments		$ 962	$ 305
Net change in cumulative foreign currency translation loss		(702)	(809)
Comprehensive income		73,709	43,806
Subscription services [Member]
Revenues:
Revenues		198,115	156,003
Cost of revenues:
Cost of revenues	[1]	30,378	29,913
Professional services and other [Member]
Revenues:
Revenues		46,637	39,544
Cost of revenues:
Cost of revenues	[1]	$ 35,125	$ 30,242

[1] Includes stock-based compensation as follows:  Cost of revenues: Cost of subscription services $385 $345 Cost of professional services and other 2,978 2,328 Research and development 6,325 4,667 Sales and marketing 5,152 4,088 General and administrative 5,916 5,583 Total stock-based compensation $20,756 $17,011