Held-to-maturity Securities, Adjustments for Fair Value Calculation [Abstract]

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Carrying amount of cash and investment securities on deposit with state regulatory authorities in connection with capital requirements.

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The amount of cash, securities, or other assets held by a third-party trustee pursuant to the terms of an agreement which assets are available to be used by beneficiaries to that agreement only within the specific terms thereof and which agreement is expected to terminate within one year of the balance sheet date (or operating cycle, if longer) at which time the assets held-in-trust will be released or forfeited.

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The amount of cash, securities, or other assets held by a third-party trustee pursuant to the terms of an agreement which assets are available to be used by beneficiaries to that agreement only within the specific terms thereof and which agreement is expected to terminate more than one year from the balance sheet date (or operating cycle, if longer) at which time the assets held-in-trust will be released or forfeited.

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Carrying amount as of the balance sheet date of assets held under deferred compensation agreements.

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Amount of investment in debt security measured at amortized cost (held-to-maturity).

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Amount of accumulated unrecognized gain on investment in debt security measured at amortized cost (held-to-maturity).

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Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity).

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Fair value of investment in debt security measured at amortized cost (held-to-maturity), with single maturity date and allocated without single maturity date, maturing in sixth through tenth 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 investment in debt security measured at amortized cost (held-to-maturity), with single maturity date and allocated without single maturity date, maturing in sixth through tenth 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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Fair value of investment in debt security measured at amortized cost (held-to-maturity), with single maturity date and allocated without single maturity date, maturing in second through 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 investment in debt security measured at amortized cost (held-to-maturity), with single maturity date and allocated without single maturity date, maturing in second through 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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Fair value of investment in debt security measured at amortized cost (held-to-maturity), with single maturity date and allocated without single maturity 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 investment in debt security measured at amortized cost (held-to-maturity), with single maturity date and allocated without single maturity 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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Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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This item represents the amount that could be realized under a life insurance contract or contracts owned by the Entity as of the date of the statement of financial position. Such Entity-owned life insurance policies are commonly known as corporate-owned life insurance (COLI) or bank-owned life insurance (BOLI).

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The noncurrent cash, cash equivalents and investments that is restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits classified as long-term; that is not expected to be released from such existing restrictions within one year of the balance sheet date or operating cycle, whichever is longer. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. Includes noncurrent cash equivalents and investments that are similarly restricted as to withdrawal, usage or disposal.

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Amount of unrealized gain (loss) on investment.

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RESTRICTED CASH AND INVESTMENTS (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 27, 2021	Jun. 28, 2020	Jun. 27, 2021	Jun. 28, 2020	Dec. 27, 2020
Restricted Cash and Investments [Line Items]
Cash collateral held by insurance carriers	$ 26,922		$ 26,922		$ 26,025
Cash and cash equivalents held in Trust	26,344		26,344		29,410
Investments held in Trust	135,894		135,894		152,247
Deferred compensation investments	6,303		6,303		5,915
Company owned life insurance policies	28,016		28,016		26,267
Other restricted cash and cash equivalents	1,170		1,170		670
Restricted cash and investments	224,649		224,649		240,534
Held-to-maturity Securities, Reconciliation to Fair Value [Abstract]
Amortized cost of held-to-maturity investments	135,894		135,894		152,247
Gross unrealized gains	4,599		4,599		6,090
Gross unrealized losses	(191)		(191)		(41)
Fair value	140,302		140,302		158,296
Held-to-maturity securities, amortized cost [Abstract]
Amortized cost of held-to-maturity investments	135,894		135,894		152,247
Held-to-maturity securities, fair value [Abstract]
Fair value	140,302		140,302		158,296
Unrealized gains (losses) on Investments	1,549	$ (3,114)	(2,426)	$ (1,727)
Municipal debt securities
Held-to-maturity Securities, Reconciliation to Fair Value [Abstract]
Amortized cost of held-to-maturity investments	61,240		61,240		67,287
Gross unrealized gains	2,686		2,686		3,436
Gross unrealized losses	0		0		0
Fair value	63,926		63,926		70,723
Held-to-maturity securities, amortized cost [Abstract]
Amortized cost of held-to-maturity investments	61,240		61,240		67,287
Held-to-maturity securities, fair value [Abstract]
Fair value	63,926		63,926		70,723
Corporate debt securities
Held-to-maturity Securities, Reconciliation to Fair Value [Abstract]
Amortized cost of held-to-maturity investments	73,396		73,396		83,467
Gross unrealized gains	1,809		1,809		2,511
Gross unrealized losses	(191)		(191)		(41)
Fair value	75,014		75,014		85,937
Held-to-maturity securities, amortized cost [Abstract]
Amortized cost of held-to-maturity investments	73,396		73,396		83,467
Held-to-maturity securities, fair value [Abstract]
Fair value	75,014		75,014		85,937
Agency mortgage-backed securities
Held-to-maturity Securities, Reconciliation to Fair Value [Abstract]
Amortized cost of held-to-maturity investments	258		258		493
Gross unrealized gains	9		9		19
Gross unrealized losses	0		0		0
Fair value	267		267		512
Held-to-maturity securities, amortized cost [Abstract]
Amortized cost of held-to-maturity investments	258		258		493
Held-to-maturity securities, fair value [Abstract]
Fair value	267		267		512
U.S. government and agency securities
Held-to-maturity Securities, Reconciliation to Fair Value [Abstract]
Amortized cost of held-to-maturity investments	1,000		1,000		1,000
Gross unrealized gains	95		95		124
Gross unrealized losses	0		0		0
Fair value	1,095		1,095		1,124
Held-to-maturity securities, amortized cost [Abstract]
Amortized cost of held-to-maturity investments	1,000		1,000		1,000
Held-to-maturity securities, fair value [Abstract]
Fair value	1,095		1,095		$ 1,124
Restricted cash and investments
Held-to-maturity Securities, Reconciliation to Fair Value [Abstract]
Amortized cost of held-to-maturity investments	135,894		135,894
Fair value	140,302		140,302
Held-to-maturity securities, amortized cost [Abstract]
Due in one year or less	21,607		21,607
Due after one year through five years	105,331		105,331
Due after five years through ten years	8,956		8,956
Amortized cost of held-to-maturity investments	135,894		135,894
Held-to-maturity securities, fair value [Abstract]
Due in one year or less	21,826		21,826
Due after one year through five years	108,987		108,987
Due after five years through ten years	9,489		9,489
Fair value	$ 140,302		$ 140,302