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Significant Accounting Policies (Basis to Determine EPS Performance Multiplier) (Details)	12 Months Ended
	Sep. 29, 2017
EPS Growth Rate | Less than 4%
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
EPS Performance Multiplier	0.00%
EPS Growth Rate | 4%
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
EPS Performance Multiplier	50.00%
EPS Growth Rate | 7.5%
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
EPS Performance Multiplier	100.00%
EPS Growth Rate | 15%
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
EPS Performance Multiplier	150.00%
EPS Growth Rate | 20% or Greater
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
EPS Performance Multiplier	200.00%
EPS Growth Rate Restricted Stock Units 2017 Awards from Fiscal 2016 to Fiscal 2017 | Less than 0%
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
EPS Performance Multiplier	0.00%
EPS Growth Rate Restricted Stock Units 2017 Awards from Fiscal 2016 to Fiscal 2017 | 2.3%
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
EPS Performance Multiplier	100.00%
EPS Growth Rate Restricted Stock Units 2017 Awards from Fiscal 2016 to Fiscal 2017 | 4.3%
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
EPS Performance Multiplier	200.00%
EPS Growth Rate Restricted Stock Units 2017 Awards from Fiscal 2016 to Fiscal 2018 | Less than 2.1%
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
EPS Performance Multiplier	0.00%
EPS Growth Rate Restricted Stock Units 2017 Awards from Fiscal 2016 to Fiscal 2018 | 2.3%
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
EPS Performance Multiplier	100.00%
EPS Growth Rate Restricted Stock Units 2017 Awards from Fiscal 2016 to Fiscal 2018 | 4.3%
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
EPS Performance Multiplier	200.00%
EPS Growth Rate Restricted Stock Units 2017 Awards from Fiscal 2016 to Fiscal 2019 | Less than 3.6%
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
EPS Performance Multiplier	0.00%
EPS Growth Rate Restricted Stock Units 2017 Awards from Fiscal 2016 to Fiscal 2019 | 5.6%
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
EPS Performance Multiplier	100.00%
EPS Growth Rate Restricted Stock Units 2017 Awards from Fiscal 2016 to Fiscal 2019 | 7.6%
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
EPS Performance Multiplier	200.00%

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