Borrowings and Credit Arrangements - Company's Borrowings (Detail) - USD ($) $ in Millions	Sep. 24, 2016	Sep. 26, 2015
Debt Instrument [Line Items]
Current debt obligations, net of debt discount	$ 296.0	$ 391.2
Convertible Notes	12.2	141.8
Convertible Notes	763.5	858.8
Total long-term debt obligations	3,049.4	3,221.0
Total debt obligations	3,345.4	3,612.2
Term Loan [Member]
Debt Instrument [Line Items]
Current debt obligations, net of debt discount	83.8	74.4
Long-term debt obligations, net of debt discount	1,308.2	1,388.3
Revolver [Member]
Debt Instrument [Line Items]
Current debt obligations, net of debt discount	0.0	175.0
Accounts Receivable Securitization [Member]
Debt Instrument [Line Items]
Current debt obligations, net of debt discount	200.0	0.0
2022 Senior Notes [Member]
Debt Instrument [Line Items]
Long-term debt obligations, net of debt discount	$ 977.7	$ 973.9

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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