The number of locations involved in a sales and leaseback transaction.

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Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation.

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Amount of gain (loss) on sale or disposal of property, plant and equipment assets, including oil and gas property and timber property.

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Amount of lease cost recognized by lessee for lease contract.

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Indicates (true false) whether lessee has option to extend operating lease.

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Amount of lessee's undiscounted obligation for lease payment for operating lease.

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Amount of lessee's undiscounted obligation for lease payment for operating lease due after fifth 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 lessee's undiscounted obligation for lease payments for operating lease, due in next rolling twelve months following latest statement of financial position date. For interim and annual periods when interim periods are reported on a rolling approach, from latest statement of financial position date.

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in fifth 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 lessee's undiscounted obligation for lease payment for operating lease to be paid in fourth 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 lessee's undiscounted obligation for lease payment for operating lease to be paid 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 of lessee's undiscounted obligation for lease payment for operating lease to be paid in second 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 lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for operating lease.

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Term of lessee's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

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Amount of operating lease expense. Excludes sublease income.

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Present value of lessee's discounted obligation for lease payments from operating lease.

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Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

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Amount of lessee's right to use underlying asset under operating lease.

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Weighted average discount rate for operating lease calculated at point in time.

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Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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The cumulative amount of the reporting entity's undistributed earnings or deficit.

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Amount of increase in right-of-use asset obtained in exchange for operating lease liability.

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Amount of short-term lease cost, excluding expense for lease with term of one month or less.

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Amount of sublease income excluding finance and operating lease expense.

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Amount of variable lease cost, excluded from lease liability, recognized when obligation for payment is incurred for finance and operating leases.

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LEASES (Details) $ in Thousands	3 Months Ended	12 Months Ended
LEASES (Details) $ in Thousands	Mar. 31, 2018 USD ($) facility	Dec. 26, 2020 USD ($)	Dec. 28, 2019 USD ($)	Dec. 29, 2018 USD ($)
Leases
Retained earnings		$ 1,182,680	$ 995,022
Right-of-use assets		77,245	80,167
Operating lease liability		$ 78,058
Lessee, Operating Lease, Existence of Option to Extend		true
Rent expense		$ 28,400	$ 29,900	$ 28,100
Operating lease weighted average remaining term		6 years 10 months 2 days	7 years 3 months 14 days
Operating lease weighted average discount rate		3.12%	3.10%
Lease costs
Operating lease cost		$ 21,594	$ 20,771
Short-term lease cost		2,863	110
Variable lease cost		3,985	1,484
Sublease Income		1,013	676
Total lease cost		27,429	21,689
Cash paid - operation leases		20,000	20,000
Right-of-use assets obtained in exchange for new operating leases		12,800	$ 33,400
Future minimum payments
2021		18,671
2022		15,219
2023		12,126
2024		9,594
2025		8,102
Thereafter		25,961
Total minimum lease payments		89,673
Less present value discount		(11,615)
Total lease liability		$ 78,058
Minimum
Leases
Length of lease (in years)		1 year
Renewal options of lease		5 years
Minimum \| Motor vehicles
Leases
Length of lease (in years)		1 year
Minimum \| Equipment
Leases
Length of lease (in years)		1 year
Minimum \| Aircraft
Leases
Length of lease (in years)		1 year
Maximum
Leases
Length of lease (in years)		10 years
Renewal options of lease		15 years
Maximum \| Motor vehicles
Leases
Length of lease (in years)		10 years
Maximum \| Equipment
Leases
Length of lease (in years)		10 years
Maximum \| Aircraft
Leases
Length of lease (in years)		10 years
Medley Florida Property
Leases
Length of lease (in years)	2 years
Property sale
Number of facilities involved in a sales and leaseback transaction \| facility	1
Sale price of property	$ 36,000
Pre-tax gain on sale of property	$ 7,000