Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended
	Dec. 29, 2019	Dec. 30, 2018
Net earnings including noncontrolling interests	$ 885.3	$ 760.4
Other comprehensive loss, net of tax:
Other comprehensive income/(loss)	111.1	(12.9)
Comprehensive income including noncontrolling interests	996.4	747.5
Comprehensive income/(loss) attributable to noncontrolling interests	(0.4)	(0.2)
Comprehensive income attributable to Starbucks	996.8	747.7
Available-for-sale Securities [Member]
Other comprehensive loss, net of tax:
Unrealized holding gains/(losses) on available-for-sale securities, before tax	(0.1)	2.2
Unrealized holding gains/(losses) on available-for-sale securities, tax (expense)/benefit	0.0	(0.5)
Cash Flow Hedging [Member]
Other comprehensive loss, net of tax:
Unrealized gains/(losses) on hedging instruments, before tax	32.4	(9.1)
Unrealized gains/(losses) on hedging instruments, tax (expense)/benefit	(6.6)	1.8
Net Investment Hedging [Member]
Other comprehensive loss, net of tax:
Unrealized gains/(losses) on hedging instruments, before tax	23.7	(21.9)
Unrealized gains/(losses) on hedging instruments, tax (expense)/benefit	(6.0)	5.6
Translation Adjustment [Member]
Other comprehensive loss, net of tax:
Translation adjustment and other, before tax	76.1	1.6
Translation adjustment and other, tax (expense)/benefit	0.0	0.0
Other comprehensive income/(loss)	76.1	1.6
Reclassification out of Accumulated Other Comprehensive Income [Member]
Other comprehensive 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	(10.7)	8.1
Reclassification adjustment for net (gains)/losses realized in net earnings for available-for-sale securities, hedging instruments, and translation adjustment, tax expense/(benefit)	$ 2.3	$ (0.7)