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Short-term and Long-term debt - Additional Information (Details)			3 Months Ended	9 Months Ended
	Mar. 02, 2022 USD ($)	Apr. 23, 2020 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2022 USD ($)
Maximum borrowing capacity	$ 90,000,000
Debt instrument, Basis spread on variable rate	2.00%
Paycheck Protection Program \| CARES Act Loan
Unsecured loan		$ 2,475,000
Term of unforgiven loan		2 years
Debt instrument interest at fixed rate		1.00%
Deferral term of unforgiven loan		9 months
Forgiveness of Payroll Protection Program Loan			$ 2,475,000
FCCR
Payment of debt, cash flow amount				$ 15,000,000
Federal Funds Purchased
Debt instrument, Basis spread on variable rate	0.50%
SOFR
Debt instrument, Basis spread on variable rate	1.00%
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 \| FILO Tranche
Additional interest percentage	6.50%
Revolving Credit Facility
Deferred financing costs	$ 200,000
2022 Term Loan Facility
Principal payments on term loan, percentage	5.00%
Percentage of excess cash flow in which annual payments made	50.00%
Prior Term Loan Facility
Deferred financing costs	$ 1,300,000
Debt instrument loan 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%
Payment of debt, cash flow amount	$ 16,000,000.0
Principal balance of debt	63,900,000
Lender fees and expenses on debt	$ 3,300,000
Credit facility, interest expense				$ 4,600,000
Minimum
Fixed charges coverage ratio				1.0
Minimum \| FCCR
Fixed charges coverage ratio				1.0
Debt instrument, leverage ratio				1.0
Minimum \| SOFR plus Applicable leverage ratio
Additional interest percentage	7.00%
Minimum \| Applicable Leverage Ratio
Additional interest percentage	6.00%
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
Fixed charges coverage ratio				5.36
Debt instrument, leverage ratio				4.00
Maximum \| SOFR plus Applicable leverage ratio
Additional interest percentage	8.00%
Maximum \| Applicable Leverage Ratio
Additional interest percentage	7.00%
Maximum \| Revolving credit facility Amendment \| SOFR
Additional interest percentage	2.86%
Maximum \| Revolving credit facility Amendment \| Prime commercial lending rate of Wells Fargo
Additional interest percentage	1.75%
Term Loan \| Minimum \| FCCR
Debt instrument, leverage ratio				0.41
Term Loan \| Maximum \| FCCR
Debt instrument, leverage ratio				1.0
Wells Fargo
Deferred financing costs	$ 900,000
Line of credit facility term	5 years
Wells Fargo \| FILO Tranche
Amount borrowed	$ 15,000,000
Wells Fargo \| FCCR
Minimum aggregate undrawn loan availability	$ 11,250,000
Period for FCCR covenant	12 months
Wells Fargo \| Revolving credit facility Amendment
Maximum borrowing capacity	$ 75,000,000
Wells Fargo \| Swing Line Loan
Maximum borrowing capacity	9,000,000
Wells Fargo \| Letter of Credit
Maximum borrowing capacity	$ 2,000,000
Wells Fargo \| Revolving Credit Facility \| FCCR
Period for FCCR covenant	2 months
Wells Fargo \| Minimum
Minimum liquidity requirement	$ 5,000,000
Wells Fargo \| Minimum \| FCCR
Fixed charges coverage ratio	1.00
Wells Fargo \| Maximum
Minimum amount to be derived from availability	$ 3,000,000
Wells Fargo \| Maximum \| FCCR
Fixed charges coverage ratio	1.00
Wells Fargo \| Maximum \| Revolving Credit Facility
Amount borrowed	$ 75,000,000