v3.23.1

Finance leases and other debt - Amended and restated loan and security agreement (Details) - USD ($)	12 Months Ended
	Jan. 31, 2023	Jan. 31, 2021	Mar. 28, 2022	Mar. 27, 2022	Jan. 31, 2022	May 05, 2020	Feb. 28, 2019
Term loan
Debt Instrument [Line Items]
Debt instrument, face amount							$ 20,000,000
Loss on extinguishment of debt		$ 1,073,000
Second SVB Facility | Revolving credit facility
Debt Instrument [Line Items]
Line of credit borrowing capacity						$ 50,000,000
Accordion feature, potential new maximum borrowing capacity						65,000,000
Long term debt	$ 0				$ 0	$ 20,663,000
Third SVB Facility | Revolving credit facility
Debt Instrument [Line Items]
Line of credit borrowing capacity			$ 100,000	$ 50,000
Stated interest rate (as a percent)	3.25%
Interest rate (as a percent)	7.00%
Annual commitment fee	$ 250,000
Unused capacity, commitment fee (as a percent)	0.15%
Remaining borrowing capacity	$ 100,000,000
Termination fee percentage (up to) (as a percent)						1.50%
Third SVB Facility | Revolving credit facility | Prime Rate
Debt Instrument [Line Items]
Scheduled reduction in interest rate (as a percent)	0.50%

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Face (par) amount of debt instrument at time of issuance.

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Incremental percentage increase (decrease) in the stated rate on a debt instrument.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

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