v3.21.1

Summary of significant accounting policies (Detail) |  | 1 Months Ended | 3 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | ---
Oct. 23, 2020 USD ($) $ / shares shares | Oct. 31, 2020 USD ($) $ / shares shares | Apr. 30, 2020 | Jan. 31, 2021 USD ($) processors segment | Jan. 31, 2020 USD ($) | Jan. 31, 2019 USD ($) | Feb. 01, 2020 USD ($)
Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Number of third party payment processors | processors |  |  |  | 1 |  |  |  |  |
Advertising expense |  |  |  | $ 558,000 |  | $ 251,000 |  | $ 134,000 |
Allowance for doubtful accounts |  |  |  | 699,000 |  | 943,000 |  |  |
Asset impairment charges |  |  |  | $ 0 |  | 0 |  | 0 |
Number of operating segment | segment |  |  |  | 1 |  |  |  |  |
Issuance of common stock, net of issuance costs (in shares) | shares | 5,750,000 | 5,750,000 |  |  |  |  |  |  |
Issue price per share (in USD per share) | $ / shares | $ 32.00 | $ 32.00 |  |  |  |  |  |  |
Net proceeds after discounts and offering expenses | $ 174,510,000 | $ 174,800,000 |  | $ 174,800,000 |  | 130,781,000 |  | $ 0 |
Lease right-of-use assets |  |  |  | 2,654,000 | [1] | $ 0 | [1] |  | $ 2,741,000
Total operating lease liabilities |  |  |  | $ 2,986,000 |  |  |  |  |
Customer Concentration Risk | Accounts Receivable | One entity |  |  |  |  |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Accounts receivable concentration percentage |  |  |  | 10.00% |  |  |  |  |
Topic 842 |  |  |  |  |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Lease right-of-use assets |  |  |  |  |  |  |  |  | 2,741,000
Total operating lease liabilities |  |  |  |  |  |  |  |  | $ 2,928,000
Internal-use software |  |  |  |  |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Estimated useful life (in years) |  |  | 3 years |  |  |  |  |  |
Minimum |  |  |  |  |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Settlement period (in days) |  |  |  | 1 day |  |  |  |  |
Useful life (years) |  |  |  | 3 years |  |  |  |  |
Maximum |  |  |  |  |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Settlement period (in days) |  |  |  | 2 days |  |  |  |  |
Useful life (years) |  |  |  | 7 years |  |  |  |  |
[1] | Figures as of January 31, 2021 reflect the Company's February 1, 2020 adoption of Accounting Standards Codification No. 842, Leases (ASC 842). For additional details, see Note 3(ac), "Summary of significant accounting policies — Impact of recently adopted accounting pronouncements."

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