Financial Instruments (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 30, 2018	Jul. 01, 2018
Debt Instrument [Line Items]
Carrying Cost	$ 1,709,895	$ 1,709,895	$ 1,709,895
Less: Deferred debt expenses	14,062	14,803	15,545
Long-term Debt, Excluding Current Maturities	1,695,833	1,695,092	1,694,350
Fair Value	1,846,794	1,685,936	1,734,634
6.35% Notes Due 2040
Debt Instrument [Line Items]
Carrying Cost	500,000	500,000	500,000
Fair Value	$ 591,850	535,000	557,250
Interest Rate	6.35%
3.50% Notes Due 2027
Debt Instrument [Line Items]
Carrying Cost	$ 500,000	500,000	500,000
Fair Value	$ 507,200	457,350	464,600
Interest Rate	3.50%
5.10% Notes Due 2044
Debt Instrument [Line Items]
Carrying Cost	$ 300,000	300,000	300,000
Fair Value	$ 310,860	272,640	287,730
Interest Rate	5.10%
3.15% Notes Due 2021
Debt Instrument [Line Items]
Carrying Cost	$ 300,000	300,000	300,000
Fair Value	$ 303,900	297,600	297,960
Interest Rate	3.15%
6.60% Debentures Due 2028
Debt Instrument [Line Items]
Carrying Cost	$ 109,895	109,895	109,895
Fair Value	$ 132,984	$ 123,346	$ 127,094
Interest Rate	6.60%

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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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 issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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