Borrowings and Credit Arrangements - Company's Borrowings (Detail) - USD ($) $ in Millions	Mar. 26, 2016	Sep. 26, 2015
Debt Instrument [Line Items]
Current debt obligations, net of debt discount	$ 307.7	$ 391.8
Convertible Notes Payable, Current	58.0	142.2
Convertible Notes	747.2	861.5
Total long-term debt obligations	3,098.0	3,248.0
Total debt obligations	3,405.7	3,639.8
Term Loan [Member]
Debt Instrument [Line Items]
Current debt obligations, net of debt discount	74.7	74.6
Long-term debt obligations, net of debt discount	1,363.1	1,399.8
Revolver [Member]
Debt Instrument [Line Items]
Current debt obligations, net of debt discount	175.0	175.0
2022 Notes [Member]
Debt Instrument [Line Items]
Long-term debt obligations, net of debt discount	$ 987.7	$ 986.7

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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+ References

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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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