Discontinued Operations - Quarterly Financial Information (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	6 Months Ended
Apr. 14, 2019	Apr. 15, 2018	Apr. 14, 2019	Apr. 15, 2018
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Basic (in usd per share)	$ 0.00	$ 0.78	$ 0.11	$ 0.75
Diluted (in usd per share)	$ 0.00	$ 0.77	$ 0.11	$ 0.74
Qdoba
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Company restaurant sales	$ 0	$ 66,850	$ 0	$ 192,620
Franchise revenues	0	3,351	0	9,337
Company restaurant costs (excluding depreciation and amortization)	0	(57,504)	0	(166,122)
Franchise costs (excluding depreciation and amortization)	0	(930)	0	(2,338)
Selling, general and administrative expenses	(59)	(5,848)	243	(18,112)
Depreciation and amortization expenses	0	0	0	(5,012)
Impairment and other charges, net	0	(594)	0	(2,263)
Interest expense, net	0	(1,575)	0	(4,787)
Operating (losses) earnings from discontinued operations before income taxes	(59)	3,750	243	3,323
Gain (loss) on Qdoba Sale	0	35,729	(85)	35,729
(Losses) earnings from discontinued operations before income taxes	(59)	39,479	158	39,052
Income taxes	18	(16,819)	2,778	(17,024)
(Losses) earnings from discontinued operations, net of income taxes	$ (41)	$ 22,660	$ 2,936	$ 22,028
Basic (in usd per share)	$ 0.00	$ 0.78	$ 0.11	$ 0.75
Diluted (in usd per share)	$ 0.00	$ 0.77	$ 0.11	$ 0.74

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