For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of transaction price allocated to performance obligation that has not been recognized as revenue.

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Period in which remaining performance obligation is expected to be recognized as revenue, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Percentage of remaining performance obligation to total remaining performance obligation not recognized as revenue.

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Revenues - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
Revenues - Narrative (Details) - USD ($) $ in Millions	Oct. 31, 2021	Oct. 31, 2020	Oct. 31, 2021	Oct. 31, 2020	Jan. 31, 2021
Disaggregation of Revenue [Line Items]
Deferred revenue recognized	$ 45.0	$ 28.0	$ 78.4	$ 53.8
Remaining performance obligation	$ 242.5		$ 242.5		$ 159.9
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-11-01
Disaggregation of Revenue [Line Items]
Remaining performance obligation, percentage	69.00%		69.00%
Period of expected satisfaction (in months)	12 months		12 months
Accounts Receivable \| Credit Concentration Risk \| Two Distribution Channels
Disaggregation of Revenue [Line Items]
Concentration risk, percentage			10.00%
United States \| Revenue from Contract with Customer Benchmark \| Geographic Concentration Risk
Disaggregation of Revenue [Line Items]
Concentration risk, percentage	85.00%	83.00%	84.00%	83.00%