Debt (Details Textual) - USD ($) $ in Thousands	Oct. 09, 2014	Jan. 01, 2022	Jan. 02, 2021
Debt Instrument [Line Items]
Unamortized discount		$ 2,412	$ 3,207
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	2,412	$ 3,207
Debt issuance costs	$ 6,200
Fair value of Senior Notes		$ 376,400

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

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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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Amount, after accumulated amortization, of debt discount.

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Fair value portion of notes payable.

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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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