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Debt - Additional Information (Details) - USD ($)					12 Months Ended
	Jun. 22, 2020	Mar. 17, 2020	Oct. 25, 2019	Jun. 24, 2016	Dec. 25, 2021	Dec. 26, 2020	Dec. 30, 2017
Debt Instrument [Line Items]
Term loans					$ 24,435,000	$ 34,569,000
Derivative, notional amount							$ 95,600,000
FRT Term Loan
Debt Instrument [Line Items]
Debt instrument, face amount			$ 23,400,000
Line of credit facility, expiration period			3 years
Long-term line of credit, quarterly repayment amount			$ 2,000,000
Interest rate at period end					1.20%
Term loans					$ 7,900,000
Building Term Loan
Debt Instrument [Line Items]
Debt instrument, face amount	$ 18,000,000
Interest rate at period end					1.85%
Term loans					$ 16,500,000
Debt instrument, term	15 years
Debt instrument, interest payment term	15 years
Debt instrument, interest rate, effective percentage		2.75%
Building Term Loan | Interest Rate Contract
Debt Instrument [Line Items]
Derivative, notional amount		$ 18,000,000			$ 18,000,000
Derivative, floor interest rate		0.00%
Derivative, floor interest rate term		1 year			1 year
LIBOR | Building Term Loan
Debt Instrument [Line Items]
Basis spread on variable rate	1.75%	1.75%			1.75%
Euro Interbank Offered Rate (EURIBOR) | FRT Term Loan
Debt Instrument [Line Items]
Basis spread on variable rate			175.00%
Senior Secured Term Loan
Debt Instrument [Line Items]
Derivative, notional amount					$ 16,500,000
Senior Secured Term Loan | CMI Term Loan
Debt Instrument [Line Items]
Debt instrument, face amount				$ 150,000,000
Interest payment term				5 years
Debt principal payable in current year, percentage				5.00%
Debt principal payable in year two, percentage				10.00%
Debt principal payable in year three, percentage				20.00%
Debt principal payable in year four, percentage				30.00%
Debt principal payable in year five, percentage				35.00%
Senior Secured Term Loan | LIBOR | CMI Term Loan
Debt Instrument [Line Items]
Basis spread on variable rate				2.00%
Senior Secured Term Loan | Base Rate | CMI Term Loan
Debt Instrument [Line Items]
Basis spread on variable rate				1.00%

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Debt Instrument, Interest Payment Term

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Long-Term Line of Credit, Quarterly Repayment Amount

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Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months, Percentage

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Long-term Debt, Maturities, Repayments of Principal in Year Five, Percentage

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Long-term Debt, Maturities, Repayments of Principal in Year Four, Percentage

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Long-term Debt, Maturities, Repayments of Principal in Year Three, Percentage

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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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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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Floor rate on an interest rate derivative such as an interest rate floor or collar. If market rates falls below the floor rate, a payment or receipt is triggered on the contract.

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Nominal or face amount used to calculate payment on derivative.

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Period remaining on line of credit facility before it terminates, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The effective interest rate at the end of the reporting period.

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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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Period between issuance and maturity of long-term debt, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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