Supplemental Consolidated Balance Sheet Information (Details) - USD ($) $ in Thousands	Apr. 12, 2020	Sep. 30, 2019	Sep. 29, 2019
Balance Sheet Related Disclosures [Abstract]
Trade	$ 46,339		$ 36,907
Notes receivable	9,589		278
Income tax receivable	1,279		160
Other	14,410		10,855
Allowance for doubtful accounts	(5,286)		(2,965)
Accounts and other receivables, net	66,331		45,235
Prepaid income taxes	12,965		579
Prepaid advertising	32		1,838
Other	5,463		6,598
Prepaid expenses	18,460		9,015
Company-owned life insurance policies	107,973		112,753
Deferred rent receivable	49,152		49,333
Franchise tenant improvement allowance	29,536		26,925
Other	24,544		17,674
Other assets, net	211,205		206,685
Insurance	27,972		27,888
Payroll and related taxes	20,808		31,095
Deferred franchise fees	4,951		4,978
Sales and property taxes	10,251		4,268
Gift card liability	2,196		2,036
Other	54,771		49,818
Accrued liabilities	120,949	$ 115,381	120,083
Defined benefit pension plans	147,295		120,260
Deferred franchise fees, Noncurrent	39,748		41,295
Straight-line rent accrual	0		29,537
Other	55,325		72,678
Other long-term liabilities	$ 242,368	$ 221,887	$ 263,770

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