RESTRICTED CASH AND INVESTMENTS (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Jan. 01, 2017
Restricted Cash and Investments [Line Items]
Cash collateral held by insurance carriers	$ 22,926	$ 34,910
Cash and cash equivalents held in Trust	16,113	32,841
Investments held in Trust	171,752	146,517
Other	28,440	16,925
Restricted cash and investments	239,231	231,193
Held-to-maturity Securities, Reconciliation to Fair Value [Abstract]
Gross Unrealized Gain	1,324	685
Gross Unrealized Loss	(838)	(1,249)
Fair Value	172,238	145,953
Held-to-maturity Securities, Investment Maturities, Fair Value [Abstract]
Fair Value	172,238	145,953
Municipal debt securities
Restricted Cash and Investments [Line Items]
Investments held in Trust	82,770	71,618
Held-to-maturity Securities, Reconciliation to Fair Value [Abstract]
Gross Unrealized Gain	974	443
Gross Unrealized Loss	(378)	(865)
Fair Value	83,366	71,196
Held-to-maturity Securities, Investment Maturities, Fair Value [Abstract]
Fair Value	83,366	71,196
Corporate debt securities
Restricted Cash and Investments [Line Items]
Investments held in Trust	83,916	68,934
Held-to-maturity Securities, Reconciliation to Fair Value [Abstract]
Gross Unrealized Gain	309	212
Gross Unrealized Loss	(434)	(352)
Fair Value	83,791	68,794
Held-to-maturity Securities, Investment Maturities, Fair Value [Abstract]
Fair Value	83,791	68,794
Agency mortgage-backed securities
Restricted Cash and Investments [Line Items]
Investments held in Trust	4,066	5,965
Held-to-maturity Securities, Reconciliation to Fair Value [Abstract]
Gross Unrealized Gain	22	30
Gross Unrealized Loss	(26)	(32)
Fair Value	4,062	5,963
Held-to-maturity Securities, Investment Maturities, Fair Value [Abstract]
Fair Value	4,062	$ 5,963
U.S. government and agency securities
Restricted Cash and Investments [Line Items]
Investments held in Trust	1,000
Held-to-maturity Securities, Reconciliation to Fair Value [Abstract]
Gross Unrealized Gain	19
Gross Unrealized Loss	0
Fair Value	1,019
Held-to-maturity Securities, Investment Maturities, Fair Value [Abstract]
Fair Value	1,019
Restricted Cash and Investments
Restricted Cash and Investments [Line Items]
Investments held in Trust	171,752
Held-to-maturity Securities, Reconciliation to Fair Value [Abstract]
Fair Value	172,238
Held-to-maturity Securities, Investment Maturities, Amortized Cost [Abstract]
Due in one year or less	17,265
Due after one year through five years	90,906
Due after five years through ten years	63,581
Held-to-maturity Securities, Investment Maturities, Fair Value [Abstract]
Due in one year or less	17,248
Due after one year through five years	90,825
Due after five years through ten years	64,165
Fair Value	$ 172,238

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 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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