Summary of Significant Accounting Policies (Narrative) (Details)	3 Months Ended	12 Months Ended
	Jul. 02, 2017 USD ($)	Sep. 30, 2018 USD ($)	Oct. 01, 2017 USD ($)	Oct. 02, 2016 USD ($)
Accounting Policies [Abstract]
Stored Value Cards and Loyalty Program		$ 155,900,000	$ 104,600,000	$ 60,500,000
Number of reportable operating segments		4
Derivative [Line Items]
Goodwill, Impairment Loss		$ 37,600,000	87,200,000	0
Derivative asset, cash collateral		5,400,000
Derivative, Collateral, Obligation to Return Cash			5,800,000
Derivative contract, potential effects of netting, reduction in value		5,500,000	7,400,000
Derivative asset		29,400,000	30,000,000
Derivative liability		44,500,000	31,100,000
Receivables, net of Allowance for Doubtful Accounts
Allowance for doubtful accounts		8,000,000	9,800,000
Inventories
Inventory reserves		41,500,000	38,400,000
Property, Plant and Equipment [Line Items]
Net disposition charges on property, plant and equipment		(32,800,000)	(46,900,000)	(25,100,000)
Net impairment charges on property, plant and equipment		42,800,000	56,100,000	24,100,000
Marketing & Advertising
Advertising expenses		260,300,000	282,600,000	$ 248,600,000
Asset Retirement Obligations
Net ARO assets included in property, plant and equipment		19,100,000	12,400,000
Net ARO liabilities included in other long-term liabilities		$ 82,400,000	70,000,000
Equipment [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life of property, plant and equipment, in years		2 years
Equipment [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life of property, plant and equipment, in years		15 years
Buildings [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life of property, plant and equipment, in years		30 years
Buildings [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life of property, plant and equipment, in years		40 years
Leasehold improvements [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life of property, plant and equipment, in years		10 years
Commodity Contract [Member] | Maximum [Member]
Derivative [Line Items]
Derivative instruments maturity, in years		3 years
Teavana [Member]
Derivative [Line Items]
Goodwill, Impairment Loss	$ 69,300,000
Starbucks Coffee Switzerland [Member]
Derivative [Line Items]
Goodwill, Impairment Loss	$ 17,900,000	$ 37,600,000
Restructuring Charges [Member]
Property, Plant and Equipment [Line Items]
Net impairment charges on property, plant and equipment		$ 37,000,000	$ 39,900,000