FAIR VALUE (Available-for-Sale Financial Instruments Measured at Fair Value) (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Investments, Debt and Equity Securities [Abstract]
Debt securities, at fair value	$ 349,299	$ 488,210
Equity securities, at fair value	5,965	3,157
Total investments, at fair value	355,264	491,367
Embedded Derivative Financial Instruments
Investments, Debt and Equity Securities [Abstract]
Other assets - embedded derivative, at fair value	10,725
United States government obligations and authorities
Investments, Debt and Equity Securities [Abstract]
Debt securities, at fair value	95,129	171,775
Obligations of states and political subdivisions
Investments, Debt and Equity Securities [Abstract]
Debt securities, at fair value	20,456	22,264
Corporate securities
Investments, Debt and Equity Securities [Abstract]
Debt securities, at fair value	202,922	266,528
International securities
Investments, Debt and Equity Securities [Abstract]
Debt securities, at fair value	30,792	27,643
Level 1
Investments, Debt and Equity Securities [Abstract]
Debt securities, at fair value	39,660	38,511
Equity securities, at fair value	2,697	1,881
Total investments, at fair value	42,357	40,392
Level 1 \| Embedded Derivative Financial Instruments
Investments, Debt and Equity Securities [Abstract]
Other assets - embedded derivative, at fair value	0
Level 1 \| United States government obligations and authorities
Investments, Debt and Equity Securities [Abstract]
Debt securities, at fair value	39,660	38,511
Level 1 \| Obligations of states and political subdivisions
Investments, Debt and Equity Securities [Abstract]
Debt securities, at fair value	0	0
Level 1 \| Corporate securities
Investments, Debt and Equity Securities [Abstract]
Debt securities, at fair value	0	0
Level 1 \| International securities
Investments, Debt and Equity Securities [Abstract]
Debt securities, at fair value	0	0
Level 2
Investments, Debt and Equity Securities [Abstract]
Debt securities, at fair value	309,639	449,699
Equity securities, at fair value	3,268	1,276
Total investments, at fair value	312,907	450,975
Level 2 \| Embedded Derivative Financial Instruments
Investments, Debt and Equity Securities [Abstract]
Other assets - embedded derivative, at fair value	0
Level 2 \| United States government obligations and authorities
Investments, Debt and Equity Securities [Abstract]
Debt securities, at fair value	55,469	133,264
Level 2 \| Obligations of states and political subdivisions
Investments, Debt and Equity Securities [Abstract]
Debt securities, at fair value	20,456	22,264
Level 2 \| Corporate securities
Investments, Debt and Equity Securities [Abstract]
Debt securities, at fair value	202,922	266,528
Level 2 \| International securities
Investments, Debt and Equity Securities [Abstract]
Debt securities, at fair value	30,792	27,643
Level 3
Investments, Debt and Equity Securities [Abstract]
Debt securities, at fair value	0	0
Equity securities, at fair value	0	0
Total investments, at fair value	0	0
Level 3 \| Embedded Derivative Financial Instruments
Investments, Debt and Equity Securities [Abstract]
Other assets - embedded derivative, at fair value	10,725
Level 3 \| United States government obligations and authorities
Investments, Debt and Equity Securities [Abstract]
Debt securities, at fair value	0	0
Level 3 \| Obligations of states and political subdivisions
Investments, Debt and Equity Securities [Abstract]
Debt securities, at fair value	0	0
Level 3 \| Corporate securities
Investments, Debt and Equity Securities [Abstract]
Debt securities, at fair value	0	0
Level 3 \| International securities
Investments, Debt and Equity Securities [Abstract]
Debt securities, at fair value	$ 0	$ 0

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(6))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=124260329&loc=d3e26610-111562

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27161-111563

+ Details

Name:	us-gaap_AvailableForSaleSecuritiesDebtSecurities
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=123594786&loc=SL75136599-209740

+ Details

Name:	us-gaap_EquitySecuritiesFvNi
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- References

No definition available.

+ Details

Name:	us-gaap_InvestmentsDebtAndEquitySecuritiesAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258

+ Details

Name:	us-gaap_InvestmentsFairValueDisclosure
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Fair value portion of other assets.

+ References

No definition available.

+ Details

Name:	us-gaap_OtherAssetsFairValueDisclosure
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	us-gaap_DerivativeInstrumentRiskAxis=us-gaap_EmbeddedDerivativeFinancialInstrumentsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_USTreasuryAndGovernmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_USStatesAndPoliticalSubdivisionsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_CorporateDebtSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_ForeignCorporateDebtSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel1Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel2Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel3Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: