Borrowings and Credit Arrangements - Company's Borrowings (Detail) - USD ($) $ in Millions	Sep. 30, 2017	Sep. 24, 2016
Debt Instrument [Line Items]
Current debt obligations, net of debt discount	$ 1,150.8	$ 296.0
Convertible Notes	484.5	12.2
Convertible Notes	0.0	763.5
Total long-term debt obligations	2,172.1	3,049.4
Total debt obligations	3,322.9	3,345.4
Term Loan
Debt Instrument [Line Items]
Current debt obligations, net of debt discount	121.3	83.8
Long-term debt obligations, net of debt discount	1,190.5	1,308.2
Revolver
Debt Instrument [Line Items]
Current debt obligations, net of debt discount	345.0	0.0
Securitization Program
Debt Instrument [Line Items]
Current debt obligations, net of debt discount	200.0	200.0
2022 Senior Notes
Debt Instrument [Line Items]
Long-term debt obligations, net of debt discount	$ 981.6	$ 977.7

Long term debt obligations without convertible notes.

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Carrying value as of the balance sheet date of long-term debt (with maturities initially due after one year or beyond the operating cycle if longer) identified as Convertible Notes Payable, excluding current portion. Convertible Notes Payable is a written promise to pay a note which can be exchanged for a specified amount of another, related security, at the option of the issuer and the holder.

+ References

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

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