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Basis Of Presentation (Details) $ in Thousands	3 Months Ended		4 Months Ended	6 Months Ended
	Apr. 15, 2018 USD ($) segment restaurant	Apr. 16, 2017 USD ($) restaurant	Jan. 21, 2018 USD ($)	Apr. 15, 2018 USD ($) restaurant	Apr. 16, 2017 USD ($) restaurant
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Number of restaurants | restaurant	2,245	2,260		2,245	2,260
Number of reportable segments | segment	1
Contractual obligation				5.00%
Incremental Corporate Advertising Contributions	$ 1,500			$ 1,800
Marketing and advertising expense	7,300	$ 9,100		16,100	$ 21,100
Excess Tax Benefit from Share-based Compensation, Operating Activities			$ (800)	800	4,034
Net assets, adjusted balance	200			200
Net periodic benefit cost excluding service cost	$ 21	$ 500		$ 49	$ 1,100
Entity Operated Units
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Number of restaurants | restaurant	188	371		188	371
Franchised Units
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Number of restaurants | restaurant	2,057	1,889		2,057	1,889

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Amount of cash outflow for realized tax benefit related to deductible compensation cost reported on the entity's tax return for equity instruments in excess of the compensation cost for those instruments recognized for financial reporting purposes.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 20
-Section 55
-Paragraph 24
-URI http://asc.fasb.org/extlink&oid=96864182&loc=d3e11374-113907

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
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