Income Taxes - Income Tax Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 26, 2020	Sep. 28, 2019	Sep. 29, 2018
Income Tax Reconciliation [Abstract]
Income tax provision at federal statutory tax rate	$ 12,728	$ 14,593	$ 15,945
Impact of Partnership income not subject to federal income taxes	(13,045)	(14,925)	(15,939)
Permanent differences	127	162	65
Change in valuation allowance	(298)	115	(21,307)
State income taxes	403	707	656
Remeasurement of net deferred tax assets	0	0	19,941
Other	(61)	205	33
Provision for income taxes - current and deferred	$ (146)	$ 857	$ (606)

Income tax reconciliation remeasurement of net deferred tax assets.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to increase (decrease) in the valuation allowance for deferred tax assets.

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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