Supplementary Balance Sheet Information (Schedule Of Other Long-Term Liabilities) (Details) - USD ($)	Sep. 30, 2017	Sep. 24, 2016
Supplementary Balance Sheet Information [Line Items]
Advance payments on purchases contracts	$ 3,185,034	$ 1,624,792
Deferred lease expense	1,913,811	1,884,501
Nonqualified investment plan liability	13,303,318	10,692,707
Other	1,867,015	1,655,285
Other long-term liabilities	42,080,066	37,659,479
Less current portion	967,518	883,892
Total other long-term liabilities	41,112,548	36,775,587
Workers' Compensation Insurance [Member]
Supplementary Balance Sheet Information [Line Items]
Self-insurance liabilities	17,147,541	18,101,931
General Liability Insurance [Member]
Supplementary Balance Sheet Information [Line Items]
Self-insurance liabilities	$ 4,663,347	$ 3,700,263

Advance payment on purchase contracts non current.

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Deferred lease expense.

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- Definition

Nonqualified investment plan liability.

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Supplementary Balance Sheet Information [Line Items]

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Carrying value as of the balance sheet date of obligations incurred through that date and due beyond one year (or beyond one operating cycle if longer) to insurance entities to mitigate potential loss from various risks or to satisfy a promise to provide certain coverages to employees.

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Amount of liabilities classified as other.

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Amount of liabilities classified as other, due within one year or the normal operating cycle, if longer.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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Obligations not otherwise itemized or categorized in the footnotes to the financial statements that are expected to be paid after one year (or the normal operating cycle, if longer), from the balance sheet date.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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