Derivative Financial Instruments Derivative Financial Instruments (Narrative) (Details) $ in Millions, ¥ in Billions			1 Months Ended	3 Months Ended	12 Months Ended
		Jul. 01, 2015 USD ($)	Jun. 28, 2015 USD ($)	Sep. 27, 2015 USD ($)	Sep. 27, 2015 USD ($)	Sep. 28, 2014 USD ($)	Sep. 29, 2013 USD ($)	Sep. 27, 2015 JPY (¥)	Sep. 27, 2015 USD ($)	Dec. 28, 2014 USD ($)
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Interest expense					$ (70.5)	$ (64.1)	$ (28.1)
Gain resulting from acquisition of joint venture					390.6	0.0	$ 0.0
Reclassification out of Accumulated Other Comprehensive Income [Member] | Net Investment Hedges [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain resulting from acquisition of joint venture	[1]				7.2	$ 0.0
Starbucks Coffee Japan Ltd [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain resulting from acquisition of joint venture					390.6
Preexisting ownership percentage						39.50%
Starbucks Coffee Japan Ltd [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member] | Net Investment Hedges [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain resulting from acquisition of joint venture					7.2
Two Point Seven Percentage Senior Notes [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Debt Instrument, Face Value						$ 0.0			$ 500.0
Stated Interest Rate								2.70%	2.70%
Debt Instrument, Maturity			Jun. 15, 2022
Four Point Three Percentage Senior Notes [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Debt Instrument, Face Value						0.0			$ 350.0
Stated Interest Rate								4.30%	4.30%
Debt Instrument, Maturity			Jun. 15, 2045
Six Point Two Five Percentage Senior Notes [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Debt Instrument, Face Value						550.0			$ 0.0
Stated Interest Rate		6.25%						6.25%	6.25%
Debt redemption, amount		$ 550.0
Interest Rate Contract [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, Notional Amount						0.0			$ 125.0
Interest Rate Contract [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member] | Cash Flow Hedges [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Interest expense				$ 2.0	$ 3.2	5.0
Interest Rate Contract [Member] | Two Point Seven Percentage Senior Notes [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, Notional Amount										$ 250.0
Interest Rate Contract [Member] | Four Point Three Percentage Senior Notes [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, Notional Amount			$ 250.0
Cross-Currency Swap [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, Notional Amount						$ 0.0		¥ 86.5	$ 717.0

[1] (1) Release of pretax cumulative net gains in AOCI related to our net investment derivative instruments used to hedge our preexisting 39.5% equity method investment in Starbucks Japan.