RESTRICTED CASH AND INVESTMENTS (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 27, 2022	Mar. 28, 2021	Dec. 26, 2021
Restricted Cash and Investments [Line Items]
Cash collateral held by insurance carriers	$ 29,133		$ 28,957
Cash and cash equivalents held in Trust	25,550		21,590
Investments held in Trust	128,798		135,419
Company owned life insurance policies	30,309		32,318
Other restricted cash and cash equivalents	2,373		2,742
Restricted cash and investments	216,163		221,026
Held-to-maturity Securities, Reconciliation to Fair Value [Abstract]
Amortized cost of held-to-maturity investments	128,798		135,419
Gross unrealized gains	480		3,228
Gross unrealized losses	(2,327)		(563)
Fair value	126,951		138,084
Held-to-maturity securities, amortized cost [Abstract]
Amortized cost of held-to-maturity investments	128,798		135,419
Held-to-maturity securities, fair value [Abstract]
Fair value	126,951		138,084
Unrealized gains (losses) on Investments	2,011	$ 877
Municipal debt securities
Held-to-maturity Securities, Reconciliation to Fair Value [Abstract]
Amortized cost of held-to-maturity investments	55,956		56,346
Gross unrealized gains	354		2,159
Gross unrealized losses	(155)		0
Fair value	56,155		58,505
Held-to-maturity securities, amortized cost [Abstract]
Amortized cost of held-to-maturity investments	55,956		56,346
Held-to-maturity securities, fair value [Abstract]
Fair value	56,155		58,505
Corporate debt securities
Held-to-maturity Securities, Reconciliation to Fair Value [Abstract]
Amortized cost of held-to-maturity investments	71,732		77,925
Gross unrealized gains	119		995
Gross unrealized losses	(2,171)		(563)
Fair value	69,680		78,357
Held-to-maturity securities, amortized cost [Abstract]
Amortized cost of held-to-maturity investments	71,732		77,925
Held-to-maturity securities, fair value [Abstract]
Fair value	69,680		78,357
Agency mortgage-backed securities
Held-to-maturity Securities, Reconciliation to Fair Value [Abstract]
Amortized cost of held-to-maturity investments	113		148
Gross unrealized gains	0		4
Gross unrealized losses	(1)		0
Fair value	112		152
Held-to-maturity securities, amortized cost [Abstract]
Amortized cost of held-to-maturity investments	113		148
Held-to-maturity securities, fair value [Abstract]
Fair value	112		152
U.S. government and agency securities
Held-to-maturity Securities, Reconciliation to Fair Value [Abstract]
Amortized cost of held-to-maturity investments	997		1,000
Gross unrealized gains	7		70
Gross unrealized losses	0		0
Fair value	1,004		1,070
Held-to-maturity securities, amortized cost [Abstract]
Amortized cost of held-to-maturity investments	997		1,000
Held-to-maturity securities, fair value [Abstract]
Fair value	1,004		$ 1,070
Restricted cash and investments
Held-to-maturity Securities, Reconciliation to Fair Value [Abstract]
Amortized cost of held-to-maturity investments	128,798
Fair value	126,951
Held-to-maturity securities, amortized cost [Abstract]
Due in one year or less	19,778
Due after one year through five years	108,002
Due after five years through ten years	1,018
Amortized cost of held-to-maturity investments	128,798
Held-to-maturity securities, fair value [Abstract]
Due in one year or less	19,833
Due after one year through five years	106,204
Due after five years through ten years	914
Fair value	$ 126,951

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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