Description of Business and Summary of Significant Accounting Policies - Concentrations of Credit Risk and Significant Customers (Details) - customer	Apr. 30, 2020	Jan. 31, 2020
Accounts Receivable \| Customer Concentration Risk
Concentration Risk [Line Items]
Number of customers	1	0

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.

No definition available.

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Balance Type:	na
Period Type:	duration