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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 825
-Section 50
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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 latest fiscal year. Excludes interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date.

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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 latest fiscal year. Excludes interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date.

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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 through fifth fiscal year following latest fiscal year. Excludes interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date.

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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 through fifth fiscal year following latest fiscal year. Excludes interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date.

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No definition available.

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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 latest fiscal year. Excludes interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date.

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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 latest fiscal year. Excludes interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date.

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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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Amount of noncurrent assets that are pledged or subject to withdrawal restrictions, classified as other.

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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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The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of investments, not including unrealized gains or losses on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity, held at each balance sheet date and included in earnings for the period.

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RESTRICTED CASH AND INVESTMENTS (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 27, 2020	Sep. 29, 2019	Sep. 27, 2020	Sep. 29, 2019	Dec. 29, 2019
Restricted Cash and Investments [Line Items]
Cash collateral held by insurance carriers	$ 25,843		$ 25,843		$ 24,612
Cash and cash equivalents held in Trust	18,543		18,543		23,681
Investments held in Trust	156,030		156,030		149,373
Deferred compensation investments	12,950		12,950		13,670
Company owned life insurance policies	12,853		12,853		13,126
Other restricted cash and cash equivalents	3,596		3,596		6,470
Restricted cash and investments	229,815		229,815		230,932
Held-to-maturity Securities, Reconciliation to Fair Value [Abstract]
Amortized cost of held-to-maturity investments	156,030		156,030		149,373
Gross unrealized gains	6,410		6,410		3,394
Gross unrealized losses	(98)		(98)		(36)
Fair value	162,342		162,342		152,731
Held-to-maturity securities, amortized cost [Abstract]
Amortized cost of held-to-maturity investments	156,030		156,030		149,373
Held-to-maturity securities, fair value [Abstract]
Fair value	162,342		162,342		152,731
Unrealized gains (losses) on Investments	1,452	$ 115	258	$ 3,078
Municipal debt securities
Held-to-maturity Securities, Reconciliation to Fair Value [Abstract]
Amortized cost of held-to-maturity investments	68,716		68,716		72,017
Gross unrealized gains	3,638		3,638		2,219
Gross unrealized losses	0		0		0
Fair value	72,354		72,354		74,236
Held-to-maturity securities, amortized cost [Abstract]
Amortized cost of held-to-maturity investments	68,716		68,716		72,017
Held-to-maturity securities, fair value [Abstract]
Fair value	72,354		72,354		74,236
Corporate debt securities
Held-to-maturity Securities, Reconciliation to Fair Value [Abstract]
Amortized cost of held-to-maturity investments	85,629		85,629		75,000
Gross unrealized gains	2,605		2,605		1,102
Gross unrealized losses	(98)		(98)		(34)
Fair value	88,136		88,136		76,068
Held-to-maturity securities, amortized cost [Abstract]
Amortized cost of held-to-maturity investments	85,629		85,629		75,000
Held-to-maturity securities, fair value [Abstract]
Fair value	88,136		88,136		76,068
Agency mortgage-backed securities
Held-to-maturity Securities, Reconciliation to Fair Value [Abstract]
Amortized cost of held-to-maturity investments	686		686		1,357
Gross unrealized gains	27		27		21
Gross unrealized losses	0		0		(2)
Fair value	713		713		1,376
Held-to-maturity securities, amortized cost [Abstract]
Amortized cost of held-to-maturity investments	686		686		1,357
Held-to-maturity securities, fair value [Abstract]
Fair value	713		713		1,376
U.S. government and agency securities
Held-to-maturity Securities, Reconciliation to Fair Value [Abstract]
Amortized cost of held-to-maturity investments	999		999		999
Gross unrealized gains	140		140		52
Gross unrealized losses	0		0		0
Fair value	1,139		1,139		1,051
Held-to-maturity securities, amortized cost [Abstract]
Amortized cost of held-to-maturity investments	999		999		999
Held-to-maturity securities, fair value [Abstract]
Fair value	1,139		1,139		$ 1,051
Restricted cash and investments
Held-to-maturity Securities, Reconciliation to Fair Value [Abstract]
Amortized cost of held-to-maturity investments	156,030		156,030
Fair value	162,342		162,342
Held-to-maturity securities, amortized cost [Abstract]
Due in one year or less	21,395		21,395
Due after one year through five years	111,992		111,992
Due after five years through ten years	22,643		22,643
Amortized cost of held-to-maturity investments	156,030		156,030
Held-to-maturity securities, fair value [Abstract]
Due in one year or less	21,605		21,605
Due after one year through five years	116,813		116,813
Due after five years through ten years	23,924		23,924
Fair value	$ 162,342		$ 162,342