Discontinued Operations (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Sep. 29, 2019	Sep. 30, 2018	Oct. 01, 2017
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income tax benefit (expense)	$ 2,863	$ (15,700)	$ 4,119
Earnings from discontinued operations, net of income taxes	$ 2,690	$ 17,032	$ 6,759
Net earnings from discontinued operations, basic (in usd per share)	$ 0.10	$ 0.60	$ 0.22
Net earnings from discontinued operations, diluted (in usd per share)	$ 0.10	$ 0.59	$ 0.22
Qdoba
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Company restaurant sales	$ 0	$ 192,620	$ 436,558
Franchise revenues	0	9,337	20,065
Company restaurant costs (excluding depreciation and amortization)	0	(166,122)	(357,370)
Franchise costs (excluding depreciation and amortization)	0	(2,338)	(4,993)
Selling, general and administrative expenses	174	(19,286)	(36,706)
Depreciation and amortization	0	(5,012)	(21,500)
Impairment and other charges, net	(262)	(2,305)	(15,061)
Interest expense, net	0	(4,787)	(9,025)
Operating (loss) earnings from discontinued operations before income taxes	(88)	2,107	11,968
(Loss) gain on Qdoba Sale	(85)	30,717	0
(Loss) earnings from discontinued operations before income taxes	(173)	32,824	11,968
Income tax benefit (expense)	2,863	(15,726)	(4,518)
Earnings from discontinued operations, net of income taxes	$ 2,690	$ 17,098	$ 7,450
Net earnings from discontinued operations, basic (in usd per share)	$ 0.10	$ 0.60	$ 0.24
Net earnings from discontinued operations, diluted (in usd per share)	$ 0.10	$ 0.59	$ 0.24

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