Balance Sheet Components - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Jan. 31, 2021	Jan. 31, 2020	Jan. 31, 2019
Property Plant And Equipment [Line Items]
Accumulated depreciation of property and equipment acquired under finance lease	$ 152.5	$ 98.0
Depreciation expense	68.1	58.2	$ 46.3
Servers and related equipment
Property Plant And Equipment [Line Items]
Gross amount of property and equipment acquired under finance lease	256.0	216.4
Depreciation expense	54.6	43.4	$ 26.3
Construction in progress
Property Plant And Equipment [Line Items]
Gross amount of property and equipment acquired under finance lease	$ 7.1	$ 16.3