Debt (Schedule of Long-term Debt including Capital Lease Obligation) (Details) - USD ($) $ in Millions	Jun. 24, 2016	Sep. 25, 2015
Long-term Debt, Current Maturities [Abstract]
Capital Lease Obligations, Current	$ 1.0	$ 1.3
Long-term Debt, Current Maturities	22.1	22.3
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net	0.4	0.0
Long-term Debt, Excluding Current Maturities [Abstract]
Total debt	6,396.0	6,606.5
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net	95.3	109.9
Capital Lease Obligations, Noncurrent	0.3	1.0
Long-term Debt, Gross	6,373.9	6,584.2
Variable Rate Receivable Securitization	235.0	153.0
Capital Lease Obligations and Vendor Financing
Long-term Debt, Excluding Current Maturities [Abstract]
Debt Issuance Costs, Net	0.0	0.0
2015 Revolving Credit Facility
Long-term Debt, Excluding Current Maturities [Abstract]
Debt Issuance Costs, Net	3.9	4.9
Long-term Debt
Long-term Debt, Excluding Current Maturities [Abstract]
Debt Issuance Costs, Net	94.9	109.9
Term Loan and New Term Loan \| Secured Debt
Long-term Debt, Current Maturities [Abstract]
Long-term Debt, Current Maturities	20.0	20.0
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net	0.4	0.0
Long-term Debt, Excluding Current Maturities [Abstract]
Total debt	1,963.5
Long-term Debt, Gross	1,943.5	1,958.5
Debt Issuance Costs, Net	37.5	44.1
4.00% Term Loan \| Secured Debt
Long-term Debt, Current Maturities [Abstract]
Long-term Debt, Current Maturities	1.1	1.0
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net	0.0	0.0
Long-term Debt, Excluding Current Maturities [Abstract]
Long-term Debt, Gross	6.3	6.9
Debt Issuance Costs, Net	0.0	0.0
Capital Lease Obligations and Vendor Financing
Long-term Debt, Current Maturities [Abstract]
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net	0.0	0.0
Receivable Securitization
Long-term Debt, Excluding Current Maturities [Abstract]
Debt Issuance Costs, Net	0.6	0.8
3.50% Senior Notes \| Senior Notes
Long-term Debt, Excluding Current Maturities [Abstract]
Long-term Debt, Gross	300.0	300.0
Debt Issuance Costs, Net	1.2	1.7
4.88% Senior Notes \| Unsecured Debt
Long-term Debt, Excluding Current Maturities [Abstract]
Long-term Debt, Gross	700.0	700.0
2020 Notes \| Senior Notes
Long-term Debt, Excluding Current Maturities [Abstract]
Debt Issuance Costs, Net	9.4	11.3
9.50% Debenture \| Debentures
Long-term Debt, Excluding Current Maturities [Abstract]
Long-term Debt, Gross	10.4	10.4
Debt Issuance Costs, Net	0.0	0.0
5.75% Senior Notes \| Senior Notes
Long-term Debt, Excluding Current Maturities [Abstract]
Long-term Debt, Gross	884.0	900.0
Debt Issuance Costs, Net	12.6	14.4
8.00% Debenture \| Debentures
Long-term Debt, Excluding Current Maturities [Abstract]
Long-term Debt, Gross	4.4	4.4
Debt Issuance Costs, Net	0.1	0.0
4.75% Senior Notes \| Senior Notes
Long-term Debt, Excluding Current Maturities [Abstract]
Long-term Debt, Gross	600.0	600.0
Debt Issuance Costs, Net	6.5	7.1
5.625% Senior Notes \| Senior Notes
Long-term Debt, Excluding Current Maturities [Abstract]
Debt Issuance Costs, Net	12.2	13.7
5.625% Senior Notes \| Unsecured Debt
Long-term Debt, Excluding Current Maturities [Abstract]
Long-term Debt, Gross	740.0	750.0
5.50% Senior Notes \| Unsecured Debt
Long-term Debt, Excluding Current Maturities [Abstract]
Long-term Debt, Gross	700.0	700.0
2025 Notes \| Senior Notes
Long-term Debt, Excluding Current Maturities [Abstract]
Debt Issuance Costs, Net	10.9	11.9
2015 Revolving Credit Facility \| Unsecured Debt
Long-term Debt, Excluding Current Maturities [Abstract]
Long-term Debt, Gross	$ 250.0	$ 500.0

Variable Rate Receivable Securitization

No definition available.

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- Definition

Amount of capital lease obligation due within one year or the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal, through the balance sheet date and due to be paid more than one year (or one operating cycle, if longer) after the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition

Amount of unamortized debt discount (premium) and debt issuance costs.

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- Definition

Represents the aggregate of total long-term debt, including current maturities and short-term debt.

+ References

No definition available.

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- Definition

Amount, after accumulated amortization, of debt issuance costs classified as current. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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

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