Selected Quarterly Financial Information (Schedule of Selected Quarterly Financial Information) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended								12 Months Ended
	Oct. 02, 2016	Jun. 26, 2016	Mar. 27, 2016	Dec. 27, 2015	Sep. 27, 2015	Jun. 28, 2015	Mar. 29, 2015	Dec. 28, 2014	Oct. 02, 2016	Sep. 27, 2015	Sep. 28, 2014
Selected Quarterly Financial Information [Abstract]
Total net revenues	$ 5,711.2	$ 5,238.0	$ 4,993.2	$ 5,373.5	$ 4,914.8	$ 4,881.2	$ 4,563.5	$ 4,803.2	$ 21,315.9	$ 19,162.7	$ 16,447.8
Operating income	1,227.5	1,022.3	864.2	1,058.0	969.4	938.6	777.5	915.5	4,171.9	3,601.0	3,081.1
Net earnings attributable to Starbucks	$ 801.0	$ 754.1	$ 575.1	$ 687.6	$ 652.5	$ 626.7	$ 494.9	$ 983.1	$ 2,817.7	$ 2,757.4	$ 2,068.1
EPS - diluted	$ 0.54	$ 0.51	$ 0.39	$ 0.46	$ 0.43	$ 0.41	$ 0.33	$ 0.65	$ 1.90	$ 1.82	$ 1.35