Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Apr. 02, 2017	Mar. 27, 2016	Apr. 02, 2017	Mar. 27, 2016
Net earnings including noncontrolling interests	$ 652.8	$ 575.0	$ 1,404.6	$ 1,262.6
Other comprehensive loss, net of tax:
Other comprehensive income/(loss)	35.9	35.9	(98.0)	10.2
Comprehensive income including noncontrolling interests	688.7	610.9	1,306.6	1,272.8
Comprehensive income/(loss) attributable to noncontrolling interests	0.0	(0.1)	(0.3)	0.0
Comprehensive income attributable to Starbucks	688.7	611.0	1,306.9	1,272.8
Available-for-sale Securities [Member]
Other comprehensive loss, net of tax:
Unrealized holding gains/(losses) on available-for-sale securities, before tax	1.9	3.8	(11.5)	4.8
Unrealized holding gains/(losses) on available-for-sale securities, tax (expense)/benefit	(0.5)	(1.4)	3.6	(1.8)
Cash Flow Hedging [Member]
Other comprehensive loss, net of tax:
Unrealized gains/(losses) on hedging instruments, before tax	(33.5)	(68.1)	80.0	(62.3)
Unrealized gains/(losses) on hedging instruments, tax (expense)/benefit	7.7	17.4	(18.8)	14.7
Net Investment Hedging [Member]
Other comprehensive loss, net of tax:
Unrealized gains/(losses) on hedging instruments, before tax	(25.2)	0.0	15.9	0.0
Unrealized gains/(losses) on hedging instruments, tax (expense)/benefit	9.3	0.0	(5.9)	0.0
Available-for-sale Securities [Member]
Other comprehensive loss, net of tax:
Other comprehensive income/(loss)	2.3	2.1	(6.4)	3.0
Cash Flow Hedging [Member]
Other comprehensive loss, net of tax:
Other comprehensive income/(loss)	(10.0)	(27.2)	10.7	(29.4)
Net Investment Hedging [Member]
Other comprehensive loss, net of tax:
Other comprehensive income/(loss)	(15.9)	0.0	10.0	0.0
Translation Adjustment [Member]
Other comprehensive loss, net of tax:
Translation adjustment and other, before tax	58.6	56.1	(113.2)	30.0
Translation adjustment and other, tax (expense)/benefit	0.9	4.9	0.9	6.6
Other comprehensive income/(loss)	59.5	61.0	(112.3)	36.6
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	20.2	27.3	(61.5)	19.5
Reclassification adjustment for net (gains)/losses realized in net earnings for available-for-sale securities, hedging instruments, and translation adjustment, tax expense/(benefit)	$ (3.5)	$ (4.1)	$ 12.5	$ (1.3)