Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2018	Oct. 01, 2017	Oct. 02, 2016
Deconsolidation, Gain (Loss), Amount	$ (499.2)	$ (93.5)	$ (6.1)
Net earnings including noncontrolling interests	4,518.0	2,884.9	2,818.9
Other comprehensive income/(loss), net of tax:
Other comprehensive income/(loss)	(174.7)	(47.2)	91.0
Comprehensive income including noncontrolling interests	4,343.3	2,837.7	2,909.9
Comprehensive income/(loss) attributable to noncontrolling interests	(0.3)	0.2	1.2
Comprehensive income attributable to Starbucks	4,343.6	2,837.5	2,908.7
Available-for-sale Securities [Member]
Other comprehensive income/(loss), net of tax:
Unrealized holding gains/(losses) on available-for-sale securities, before tax	(7.0)	(9.5)	3.5
Unrealized holding gains/(losses) on available-for-sale securities, tax (expense)/benefit	1.9	2.9	(1.3)
Cash Flow Hedging [Member]
Other comprehensive income/(loss), net of tax:
Unrealized gains/(losses) on hedging instruments, before tax	24.4	53.2	(109.6)
Unrealized gains/(losses) on hedging instruments, tax (expense)/benefit	(6.5)	(12.6)	27.5
Net Investment Hedges [Member]
Other comprehensive income/(loss), net of tax:
Unrealized gains/(losses) on hedging instruments, before tax	7.8	20.1	0.0
Unrealized gains/(losses) on hedging instruments, tax (expense)/benefit	(2.2)	(7.4)	0.0
Translation Adjustment [Member]
Other comprehensive income/(loss), net of tax:
Translation adjustment and other, before tax	(220.0)	(38.3)	85.5
Translation adjustment and other, tax (expense)/benefit	3.4	(2.4)	19.0
Other comprehensive income/(loss)	(199.7)	(41.3)	104.5
Reclassification out of Accumulated Other Comprehensive Income [Member]
Other comprehensive income/(loss), net of tax:
Reclassification adjustment for net gains (losses) realized in net earnings for available-for-sale securities, hedging instruments, and translation adjustment, before tax	24.7	(67.2)	78.2
Reclassification adjustment for net gains (losses) realized in net earnings for available-for-sale securities, hedging instruments, and translation adjustment, tax expense/(benefit)	$ (1.2)	$ 14.0	$ (11.8)