Long-term Debt - Narrative (Details) - USD ($)	9 Months Ended	12 Months Ended
Oct. 04, 2020	Sep. 29, 2019	Dec. 29, 2019
Debt Instrument [Line Items]
Debt issuance costs	$ (1,519,000)	$ 0
Other Line Of Credit
Debt Instrument [Line Items]
Revolving loan borrowings under the Facility	0		$ 0
Line of credit facility, maximum borrowing capacity	$ 9,600,000		$ 9,500,000
Other Line Of Credit \| Minimum
Debt Instrument [Line Items]
Line of credit facility, interest rate during period (percentage)	2.00%		2.00%
Other Line Of Credit \| Maximum
Debt Instrument [Line Items]
Line of credit facility, interest rate during period (percentage)	6.00%		6.00%
Syndicated Facility Agreement
Debt Instrument [Line Items]
Debt Issuance Costs, Line of Credit Arrangements, Net	$ 1,500,000		$ 1,300,000
Revolving loan borrowings under the Facility	23,700,000		20,900,000
Letters of credit outstanding	$ 1,600,000		$ 2,200,000
Long-term debt, weighted average interest rate, at point in time (percentage)	3.15%		3.27%
Interest Rate Floor Minimum	0.00%
Interest Rate Floor Maximum	0.75%
Debt issuance costs	$ (1,500,000)
Syndicated Facility Agreement \| Term Loan
Debt Instrument [Line Items]
Unamortized debt costs	5,900,000		$ 6,300,000
Term loan borrowings outstanding	$ 562,300,000		$ 581,600,000

Interest Rate Floor Maximum

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Interest Rate Floor Minimum

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount, after accumulated amortization, of debt discount (premium).

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- Definition

Amount, after accumulated amortization, of debt issuance costs related to line of credit arrangements. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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The effective interest rate during 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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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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- Definition

Weighted average interest rate of long-term debt outstanding calculated at point in time.

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The cash outflow paid to third parties in connection with debt origination, which will be amortized over the remaining maturity period of the associated long-term debt.

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