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Employee Benefit Plans (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2017	Sep. 24, 2016	Sep. 26, 2015
Investment/Profit Sharing Plan [Member]
Postemployment and Postretirement Benefit Plans [Line Items]
Operating and administrative expenses	$ 2,400	$ 1,800	$ 1,600
Nonqualified Investment Plan [Member]
Postemployment and Postretirement Benefit Plans [Line Items]
Operating and administrative expenses	159	110	99
Cash Bonuses [Member]
Postemployment and Postretirement Benefit Plans [Line Items]
Operating and administrative expenses	$ 10,600	$ 10,600	$ 10,100

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- References

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- Definition

Amount of discretionary contributions made by an employer to a defined contribution plan.

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