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Stock-Based Compensation (Stock Options & Restricted Stock Units) (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Oct. 03, 2020	Sep. 28, 2019	Sep. 29, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	3 years
Weighted average per share fair value of stock options granted (in dollar per share)	$ 9.24	$ 9.91	$ 11.10
Weighted average remaining contractual term of options outstanding, in years	4 years
Aggregate intrinsic value of options outstanding	$ 0
Weighted average remaining contractual term of options eligible for exercise, in years	2 years 9 months 18 days
Aggregate intrinsic value of options eligible for exercise	$ 0
Total intrinsic value of stock options exercised	$ 12	$ 459	$ 121
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiration period	5 years
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiration period	7 years
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	1 year
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	3 years
Director \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights	vest one year from the date of the grant, provided such director continues to serve on the Board of Directors
Key Employees \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	3 years
Key Employees \| Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights	based on attainment of average return on invested capital performance targets over a three year performance period