Borrowings and Credit Arrangements - Company's Borrowings (Detail) - USD ($) $ in Millions	Dec. 26, 2015	Sep. 26, 2015
Debt Instrument [Line Items]
Current debt obligations, net of debt discount	$ 393.3	$ 391.8
Convertible Notes Payable, Current	143.6	142.2
Convertible Notes	870.5	861.5
Total long-term debt obligations	3,239.1	3,248.0
Total debt obligations	3,632.4	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	1,381.4	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	$ 987.2	$ 986.7

Long term debt obligations without convertible notes.

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+ 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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