Goodwill and Acquired Intangible Assets, Net - Schedule of Intangible Assets (Details) - USD ($) $ in Thousands	Apr. 30, 2020	Jan. 31, 2020
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	$ 50,055	$ 50,055
Accumulated Amortization	(17,405)	(15,276)
Net Book Value	32,650	34,779
Developed technology
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	34,700	34,700
Accumulated Amortization	(12,860)	(11,495)
Net Book Value	21,840	23,205
Domain name
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	155	155
Accumulated Amortization	(155)	(151)
Net Book Value	0	4
Customer relationships
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	15,200	15,200
Accumulated Amortization	(4,390)	(3,630)
Net Book Value	$ 10,810	$ 11,570