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Short-term and long-term debt - Additional Information (Details) - USD ($)			6 Months Ended
	Mar. 02, 2022	Apr. 23, 2020	Jun. 30, 2022	Mar. 03, 2022
Line of Credit Facility, Maximum Borrowing Capacity	$ 90,000,000
Debt Instrument, Basis Spread on Variable Rate	2.00%
Paycheck Protection Program [Member] \| CARES Act Loan [Member]
Debt Instrument, Interest Rate, Stated Percentage		1.00%
Unsecured loan		$ 2,475,000
Term of unforgiven loan		2 years
Deferral term of unforgiven loan		9 months
Forgiveness of Payroll Protection Program Loan			$ 2,475,000
FCCR [Member]
Payment of debt, cash flow amount			$ 15,000,000
Federal Funds Purchased [Member]
Debt Instrument, Basis Spread on Variable Rate	0.50%
SOFR
Debt Instrument, Basis Spread on Variable Rate	1.00%
Applicable leverage ratio
Additional interest percentage	7.00%
Revolving credit facility Amendment
Debt Instrument, Basis Spread on Variable Rate	1.00%
Additional interest percentage	0.50%
Revolving credit facility Amendment \| SOFR
Additional interest percentage	1.00%
Revolving credit facility Amendment \| SOFR \| FILO Tranche
Debt Instrument, Basis Spread on Variable Rate	1.00%
Additional interest percentage	0.50%
Revolving credit facility Amendment \| SOFR \| SOFR FILO Tranche
Additional interest percentage	7.50%
Revolving credit facility Amendment \| Prime commercial lending rate of Wells Fargo
Additional interest percentage	1.75%
Revolving credit facility Amendment \| Prime commercial lending rate of Wells Fargo \| FILO Tranche
Additional interest percentage	6.50%
Prior Term Loan Facility
Debt Instrument, Face Amount	$ 85,000,000
Payment of term loan deferred financing costs	4,300,000
Prepayment premium percentage year one			3.00%
Prepayment premium percentage year two			2.00%
Prepayment premium percentage year three			1.00%
Prepayment premium percentage year four and thereafter			0.00%
Principal payments on term loan, percentage			50.00%
Principal balance of debt	63,900,000
Payment of debt, cash flow amount	16,000,000.0
Lender fees and expenses on debt	3,300,000
Deferred financing costs	1,300,000
Credit facility, interest expense			$ 4,700,000
Revolving Credit Facility
Deferred financing costs	$ 200,000
2022 term Loan Facility
Principal payments on term loan, percentage			5.00%
Minimum
Additional interest percentage	7.00%
Fixed Charges Coverage Ratio			1.0
Minimum \| FCCR [Member]
Debt Instrument, Leverage Ratio, Required			1.0
Fixed Charges Coverage Ratio			1.0
Minimum \| Applicable leverage ratio
Additional interest percentage	6.00%
Minimum \| SOFR plus Applicable leverage ratio
Additional interest percentage				7.00%
Minimum \| Revolving credit facility Amendment \| SOFR
Additional interest percentage	2.36%
Minimum \| Revolving credit facility Amendment \| Prime commercial lending rate of Wells Fargo
Additional interest percentage	1.25%
Maximum
Fixed Charges Coverage Ratio			1.10
Maximum \| FCCR [Member]
Debt Instrument, Leverage Ratio, Required			4.00
Fixed Charges Coverage Ratio			5.30
Maximum \| SOFR plus Applicable leverage ratio
Additional interest percentage	8.00%
Maximum \| Revolving credit facility Amendment \| SOFR
Additional interest percentage	2.86%
Term Loan \| Minimum \| FCCR [Member]
Debt Instrument, Leverage Ratio, Required			0.73
Term Loan \| Maximum \| FCCR [Member]
Debt Instrument, Leverage Ratio, Required			1.0
Wells Fargo
Line of credit facility term	5 years
Deferred financing costs	$ 900,000
Wells Fargo \| FILO Tranche
Amount borrowed	15,000,000
Wells Fargo \| FCCR [Member]
Minimum aggregate undrawn loan availability	$ 11,250,000
Period for FCCR covenant	12 months
Wells Fargo \| Amended And Restated Revolving Credit And Security Agreement
Line of Credit Facility, Maximum Borrowing Capacity	$ 75,000,000
Wells Fargo \| Swing Line Loan [Member]
Line of Credit Facility, Maximum Borrowing Capacity			$ 9,000,000
Wells Fargo \| Letter of Credit [Member]
Line of Credit Facility, Maximum Borrowing Capacity			$ 2,000,000
Wells Fargo \| Revolving Credit Facility \| FCCR [Member]
Period for FCCR covenant	2 months
Wells Fargo \| Minimum
Minimum amount to be derived from availability	$ 5,000,000
Wells Fargo \| Minimum \| FCCR [Member]
Fixed Charges Coverage Ratio	1.00
Wells Fargo \| Maximum
Minimum amount to be derived from availability	$ 3,000,000
Wells Fargo \| Maximum \| FCCR [Member]
Fixed Charges Coverage Ratio	1.00
Wells Fargo \| Maximum \| Revolving Credit Facility
Amount borrowed	$ 75,000,000