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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LONG-TERM DEBT (Details) - USD ($)	12 Months Ended
LONG-TERM DEBT (Details) - USD ($)	Dec. 28, 2019	Jun. 29, 2019	Dec. 29, 2018	Jun. 19, 2018
Long-term debt:
Debt issuance costs	$ (7,786,000)		$ (8,068,000)
Total long-term debt	765,704,000		742,601,000
Less current installments of long-term debt	760,000		779,000
Long-term debt, excluding current installments	$ 764,944,000		$ 741,822,000
Effective interest rate	2.73%		3.27%
Minimum aggregate maturities of long-term debt
2020	$ 760,000
2021	761,000
2022	568,000
2023	0
2024	$ 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
Debt Instrument, Unamortized Discount	$ 7,468,000
Interest rate on notes	5.25%
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	$ (21,143,000)		$ (21,468,000)
Revolving credit agreement
Long-term debt:
Total long-term debt	29,044,000		5,719,000
Outstanding line of credit	14,608,000
Unused and available borrowings	$ 556,569,000
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	1.65%
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	$ 8,500,000		8,500,000
Other notes
Long-term debt:
Total long-term debt	2,089,000		2,918,000
Short Term Bank Lines Of Credit
Long-term debt:
Balance	132,849,000
Unused and available borrowings	111,075,000
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	$ 200,000,000
Debt Instrument, Unamortized Discount	13,675,000
Interest rate on notes			5.00%
Senior Unsecured Notes 5.25% Due 2054 \| Senior Notes
Long-term debt:
Aggregate amount	305,000,000		$ 305,000,000	$ 55,000,000
Interest rate on notes			5.25%
Revolving Credit Facility
Long-term debt:
Total line of credit facility for short-term borrowings	600,000
Unused and available borrowings	400,000
Additional borrowing capacity	200,000
Revolving Credit Facility \| Revolving credit agreement
Long-term debt:
Outstanding line of credit	$ 29,044,000