Debt Debt (Summary of long-term debt maturities) (Details) - USD ($) $ in Millions	Sep. 29, 2019	Sep. 30, 2018
Debt Instrument [Line Items]
Hedging Liabilities, Noncurrent	$ 11.8	$ (39.0)
Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months	0.0
2021	1,250.0
2022	500.0
2023	1,000.0
2024	1,538.3
Thereafter	6,950.0
Total	11,238.3	9,548.4
Three Point Seven Five Percentage Senior Notes [Member]
Debt Instrument [Line Items]
Face value of Senior Notes	$ 500.0	500.0
Stated Interest Rate	3.75%
Debt Instrument, Interest Rate, Effective Percentage	3.765%
Three Point Five Percentage Senior Notes [Member]
Debt Instrument [Line Items]
Face value of Senior Notes	$ 600.0	600.0
Stated Interest Rate	3.50%
Debt Instrument, Interest Rate, Effective Percentage	3.529%
PointThreeSevenTwoPercentageYenDenominatedSeniorNotes [Member]
Debt Instrument [Line Items]
Face value of Senior Notes	$ 788.3	748.4
Stated Interest Rate	0.372%
Debt Instrument, Interest Rate, Effective Percentage	0.462%
Three Point Eight Percentage Senior Notes [Member]
Debt Instrument [Line Items]
Face value of Senior Notes	$ 1,250.0	1,250.0
Stated Interest Rate	3.80%
Debt Instrument, Interest Rate, Effective Percentage	3.721%
Four Point Zero Percentage Senior Notes [Member]
Debt Instrument [Line Items]
Face value of Senior Notes	$ 750.0	750.0
Stated Interest Rate	4.00%
Debt Instrument, Interest Rate, Effective Percentage	3.958%
Four Point Five Percentage Senior Notes [Member]
Debt Instrument [Line Items]
Face value of Senior Notes	$ 1,000.0	1,000.0
Stated Interest Rate	4.50%
Debt Instrument, Interest Rate, Effective Percentage	4.504%
Four Point Four Five Percentage Senior Notes [Member] [Member]
Debt Instrument [Line Items]
Face value of Senior Notes	$ 1,000.0	0.0
Stated Interest Rate	4.45%
Debt Instrument, Interest Rate, Effective Percentage	4.433%
Three Point Five Five Percentage Senior Notes [Member] [Member]
Debt Instrument [Line Items]
Face value of Senior Notes	$ 1,000.0	0.0
Stated Interest Rate	3.55%
Debt Instrument, Interest Rate, Effective Percentage	3.871%
Fair Value, Inputs, Level 2 [Member] \| Three Point Seven Five Percentage Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Fair Value Disclosure	$ 518.0	438.0
Fair Value, Inputs, Level 2 [Member] \| Three Point Five Percentage Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Fair Value Disclosure	644.0	576.0
Fair Value, Inputs, Level 2 [Member] \| PointThreeSevenTwoPercentageYenDenominatedSeniorNotes [Member]
Debt Instrument [Line Items]
Debt Instrument, Fair Value Disclosure	795.0	743.0
Fair Value, Inputs, Level 2 [Member] \| Three Point Eight Percentage Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Fair Value Disclosure	1,351.0	1,249.0
Fair Value, Inputs, Level 2 [Member] \| Four Point Zero Percentage Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Fair Value Disclosure	837.0	754.0
Fair Value, Inputs, Level 2 [Member] \| Four Point Five Percentage Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Fair Value Disclosure	1,160.0	977.0
Fair Value, Inputs, Level 2 [Member] \| Four Point Four Five Percentage Senior Notes [Member] [Member]
Debt Instrument [Line Items]
Debt Instrument, Fair Value Disclosure	1,165.0	0.0
Fair Value, Inputs, Level 2 [Member] \| Three Point Five Five Percentage Senior Notes [Member] [Member]
Debt Instrument [Line Items]
Debt Instrument, Fair Value Disclosure	$ 1,080.0	$ 0.0

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.

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Fair value of liability arising from a financial instrument or contract used to mitigate a specified risk (hedge), expected to be settled after one year or beyond the normal operating cycle, if longer.

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