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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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Finance leases and other debt - Narrative (Details) - USD ($)		6 Months Ended
	Dec. 04, 2023	Jul. 31, 2024	Jan. 31, 2024	Mar. 28, 2022	Mar. 27, 2022	May 05, 2020	Feb. 28, 2019
Debt Instrument [Line Items]
Debt		$ 2,600,000
Term Loan
Debt Instrument [Line Items]
Debt instrument, face amount							$ 20,000,000
Financing arrangements
Debt Instrument [Line Items]
Debt		2,539,000	$ 3,124,000
Debt instrument, monthly payment		$ 123,000
Debt instrument, term		36 months
Effective interest rate (as a percent)		10.50%
Revolving Credit Facility \| Second SVB Facility
Debt Instrument [Line Items]
Maximum borrowing capacity						$ 50,000,000
Revolving Credit Facility \| Third SVB Facility
Debt Instrument [Line Items]
Maximum borrowing capacity				$ 100,000,000	$ 50,000,000
Stated interest rate (as a percent)		3.25%
Scheduled reduction in interest rate (as a percent)		0.50%
Annual fee amount		$ 250,000
Quarterly fee (as a percent)		0.15%
Line of Credit \| Senior Secured Asset-based Revolving Credit Facility \| Revolving Credit Facility
Debt Instrument [Line Items]
Debt instrument, term	5 years
Maximum borrowing capacity	$ 50,000
Quarterly fee (as a percent)	0.25%
Effective interest rate (as a percent)		8.40%
Debt issuance costs	$ 778,000
Line of Credit \| Senior Secured Asset-based Revolving Credit Facility \| Bridge Loan
Debt Instrument [Line Items]
Maximum borrowing capacity	5,000
Line of Credit \| Senior Secured Asset-based Revolving Credit Facility \| Letter of Credit
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 5,000