Long-Term Debt (Schedule of Long-Term Debt And Short-Term Loans) (Details) - USD ($)	Sep. 30, 2017	Sep. 24, 2016
Debt Instrument [Line Items]
Less unamortized prepaid loan costs	$ (7,221,134)	$ (8,105,090)
Total long-term debt	877,870,315	876,474,094
Less current portion	12,210,571	10,000,629
Long-term debt, net of current portion	865,659,744	866,473,465
Senior Notes, Interest Rate of 5.75%, Maturing 2023 [Member]
Debt Instrument [Line Items]
Bonds payable	$ 700,000,000	$ 700,000,000
Interest rate	5.75%	5.75%
Recovery Zone Facility Bonds, maturing 2036 [Member]
Debt Instrument [Line Items]
Bonds payable	$ 81,620,000	$ 86,150,000
Line of Credit Payable [Member]
Debt Instrument [Line Items]
Weighted average interest rate	4.25%
Notes Payable Due to Banks, Weighted Average Interest Rate of 3.24% for 2017 and 3.38% for 2016 [Member]
Debt Instrument [Line Items]
Notes payable	$ 103,471,449	$ 98,429,184
Weighted average interest rate	3.24%	3.38%

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Weighted average interest rate of debt outstanding.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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