Equity (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Oct. 01, 2017	Oct. 02, 2016
Equity [Abstract]
Authorized shares of common stock	2,400,000,000	2,400,000,000
Common stock, par value	$ 0.001	$ 0.001
Authorized shares of preferred stock	7,500,000
Outstanding shares of preferred stock	0
Increase in share of net assets of Starbucks Japan at IPO	$ 39.4	$ 39.4
Other Additional Capital related to difference between carrying value of noncontrolling interest and cash paid to acquire the noncontrolling interest	$ 1.7	$ 1.7
Shares of common stock repurchased	37,500,000	34,900,000
Total cost of common stock repurchased	$ 2,100.0	$ 2,000.0
Shares available for repurchase	80,300,000