Geographic Information - Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 31, 2020	Oct. 31, 2019	Oct. 31, 2020	Oct. 31, 2019
Revenues from External Customers and Long-Lived Assets
Revenue	$ 159,624	$ 73,012	$ 401,584	$ 177,056
United States
Revenues from External Customers and Long-Lived Assets
Revenue	135,427	64,102	341,892	158,207
Other
Revenues from External Customers and Long-Lived Assets
Revenue	$ 24,197	$ 8,910	$ 59,692	$ 18,849