Operating (Gains), Losses and Other Charges, Net (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 26, 2019	Jun. 27, 2018	Jun. 26, 2019	Jun. 27, 2018	Dec. 26, 2018
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gains on sales of assets and other, net	$ (26,839)	$ (27)	$ (36,314)	$ (64)
Restructuring charges and exit costs	406	408	946	768
Impairment charges	0	81	0	118
Operating (gains), losses and other charges, net	(26,433)	462	(35,368)	822
Restructuring Charges [Abstract]
Exit costs	52	275	174	299
Severance and other restructuring charges	354	133	772	469
Restructuring charges and exit costs	406	408	946	768
Exit cost liabilities	100		100		$ 1,200
Accrued severance and other restructuring charges	600		600		$ 600
Franchisor Owned Outlet [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gains on sales of assets and other, net	(24,228)	0	(26,432)	0
Real Estate [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gains on sales of assets and other, net	$ (3,088)	$ 0	$ (10,586)	$ 0

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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