Financing (Composition of Notes and Debentures) (Details) (USD $) In Millions, unless otherwise specified	Sep. 06, 2014	Dec. 28, 2013
Debt Instrument [Line Items]
Commercial paper	$ 0	$ 0
Bank credit agreement, unsecured	0	0
Term credit agreement, unsecured	0	400.0
Other notes payable, unsecured	21.7	21.4
Long-term debt, total	2,356.6	3,768.2
Less current maturities	(1.8)	(252.9)
Long-term portion	2,354.8	3,515.3
Mortgages [Member]
Debt Instrument [Line Items]
Mortgage notes payable, secured	4.9	46.8
Senior notes [Member] \| 5.625% Senior Notes due August 2014, unsecured [Member]
Debt Instrument [Line Items]
Senior Notes	0	250.0
Fixed interest rate of debt	5.625%	5.625%
Senior notes [Member] \| 3.40% Senior Notes due 2016, unsecured [Member]
Debt Instrument [Line Items]
Senior Notes	80.0	400.0
Fixed interest rate of debt	3.40%	3.40%
Senior notes [Member] \| 6.35% Senior Notes due 2017, unsecured [Member]
Debt Instrument [Line Items]
Senior Notes	100.0	500.0
Fixed interest rate of debt	6.35%	6.35%
Senior notes [Member] \| 5.00% Senior Notes due 2019, unsecured [Member]
Debt Instrument [Line Items]
Senior Notes	500.0	500.0
Fixed interest rate of debt	5.00%	5.00%
Senior notes [Member] \| 3.95% Senior Notes due 2020, unsecured [Member]
Debt Instrument [Line Items]
Senior Notes	500.0	500.0
Fixed interest rate of debt	3.95%	3.95%
Senior notes [Member] \| 4.75% Senior Notes due 2021, unsecured [Member]
Debt Instrument [Line Items]
Senior Notes	400.0	400.0
Fixed interest rate of debt	4.75%	4.75%
Senior Debentures [Member] \| 7.45% Senior Debentures due 2027, unsecured [Member]
Debt Instrument [Line Items]
Senior Debentures	150.0	150.0
Fixed interest rate of debt	7.45%	7.45%
Senior Debentures [Member] \| 7.25% Senior Debentures due 2031, unsecured [Member]
Debt Instrument [Line Items]
Senior Debentures	$ 600.0	$ 600.0
Fixed interest rate of debt	7.25%	7.25%

Debt Instrument, Borrowings Outstanding Under Term Credit Agreement

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- Definition

Senior Debentures

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No definition available.

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- Definition

Carrying value as of the balance sheet date of long-term unsecured obligations issued by corporations and other borrowers to investors (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion.

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- Definition

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

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- Definition

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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- Definition

Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Carrying amount of long-term debt, net of unamortized discount or premium, excluding amounts to be repaid within one year or the normal operating cycle, if longer (current maturities). Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

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Carrying value as of the balance sheet date of the portion of long-term debt not otherwise specified in the taxonomy that is scheduled to be repaid within one year or the normal operating cycle, if longer.

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Including the current and noncurrent portions, the carrying value of notes payable which were initially due after one year or beyond the normal operating cycle, if longer, and which are not otherwise defined in the taxonomy.

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Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

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- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

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