Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Face (par) amount of debt instrument at time of issuance.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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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 current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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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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Line of Credit, Additional Borrowing Capacity

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LONG-TERM DEBT (Details) - USD ($)	12 Months Ended
LONG-TERM DEBT (Details) - USD ($)	Dec. 26, 2020	Dec. 28, 2019	Jun. 29, 2019
Long-term debt:
Debt issuance costs	$ (7,505,000)	$ (7,786,000)
Total long-term debt	731,179,000	765,704,000
Less current installments of long-term debt	2,748,000	760,000
Long-term debt, excluding current installments	728,431,000	764,944,000
Minimum aggregate maturities of long-term debt
2021	2,748,000
2022	1,028,000
2023	707,000
2024	0
2025	$ 0
Senior Unsecured Notes 5.00% Due 2044
Long-term debt:
Interest rate on notes	5.00%
Redemption price of notes, stated as a percentage of principal amount	100.00%
Senior Unsecured Notes 5.25% Due 2054
Long-term debt:
Aggregate amount	$ 305,000,000
Interest rate on notes	5.25%
Unamortized debt discount	$ 7,394,000
Redemption price of notes, stated as a percentage of principal amount	100.00%
Unamortized discount on 5.00% and 5.25% senior unsecured notes
Long-term debt:
Unamortized premium on senior unsecured notes	$ (20,799,000)	(21,143,000)
Revolving credit agreement
Long-term debt:
Total long-term debt	0	29,044,000
Outstanding line of credit	14,581,000
Unused and available borrowings	$ 585,419,000
Revolving credit agreement \| Minimum
Long-term debt:
Basis points added to variable rate	0.00%
Revolving credit agreement \| Maximum
Long-term debt:
Basis points added to variable rate	0.625%
Revolving credit agreement \| LIBOR
Long-term debt:
Variable interest rate basis	LIBOR (based on a 1, 2, 3 or 6 month interest period, as selected by the Company)
Basis points added to variable rate	1.00%
Variable interest rate, base period	1 month
Revolving credit agreement \| LIBOR \| Minimum
Long-term debt:
Basis points added to variable rate	1.00%
Revolving credit agreement \| LIBOR \| Maximum
Long-term debt:
Basis points added to variable rate	1.625%
Revolving credit agreement \| Prime lending rate
Long-term debt:
Variable interest rate basis	prime lending rate
Revolving credit agreement \| Federal Funds rate
Long-term debt:
Variable interest rate basis	Federal Funds rate
Basis points added to variable rate	0.50%
IDR Bonds
Long-term debt:
Total long-term debt	$ 0	8,500,000
Other notes
Long-term debt:
Total long-term debt	4,483,000	2,089,000
Short Term Bank Lines Of Credit
Long-term debt:
Balance	144,690,000
Unused and available borrowings	109,673,000
Senior Unsecured Notes 5.00% Due 2044
Long-term debt:
Interest rate on notes			5.00%
Senior Unsecured Notes 5.00% Due 2044 \| Senior Notes
Long-term debt:
Aggregate amount	450,000,000	450,000,000
Unamortized debt discount	13,405,000
Senior Unsecured Notes 5.25% Due 2054 \| Senior Notes
Long-term debt:
Aggregate amount	305,000,000	$ 305,000,000
Revolving Credit Facility
Long-term debt:
Total line of credit facility for short-term borrowings	600,000
Additional borrowing capacity	200,000
Unused and available borrowings	400,000
Revolving Credit Facility \| Revolving credit agreement
Long-term debt:
Outstanding line of credit	$ 0