Debt (Details Textual) - USD ($) $ in Thousands	Oct. 09, 2014	Dec. 28, 2019	Dec. 29, 2018
Debt Instrument [Line Items]
Unamortized discount		$ 3,981	$ 4,709
Senior Notes [Member] \| Senior Notes Due 2024 [Member]
Debt Instrument [Line Items]
Aggregate principal amount issued	$ 350,000	350,000	350,000
Stated interest rate of Senior Notes	4.375%
Proceeds from Senior Notes, net	$ 342,400
Unamortized discount	1,400	3,981	$ 4,709
Debt issuance costs	$ 6,200
Fair value of notes payable		$ 378,400

Face (par) amount of debt instrument at time of issuance.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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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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No definition available.

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Amount, after accumulated amortization, of debt discount.

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Fair value portion of notes payable.

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The cash inflow from additional borrowings, net of cash paid to third parties in connection with debt origination.

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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