FAIR VALUE OF FINANCIAL INSTRUMENTS (Commercial Mortgage Loans) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Commercial mortgage loans, gross	$ 25,828	$ 0
Commercial mortgage loans, allowance	(46)	0
Commercial mortgage loans, amortized cost	$ 25,782	$ 0
Commercial mortgage loans, percent of total	100.00%	0.00%
Multifamily
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Commercial mortgage loans, gross	$ 3,244	$ 0
Commercial mortgage loans, percent of total	12.60%	0.00%
Office
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Commercial mortgage loans, gross	$ 11,627	$ 0
Commercial mortgage loans, percent of total	45.00%	0.00%
Mixed use/Other
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Commercial mortgage loans, gross	$ 10,957	$ 0
Commercial mortgage loans, percent of total	42.40%	0.00%
East North Central
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Commercial mortgage loans, gross	$ 3,244	$ 0
Commercial mortgage loans, percent of total	12.60%	0.00%
Southern Atlantic
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Commercial mortgage loans, gross	$ 6,652	$ 0
Commercial mortgage loans, percent of total	25.80%	0.00%
East South Central
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Commercial mortgage loans, gross	$ 4,975	$ 0
Commercial mortgage loans, percent of total	19.30%	0.00%
New England
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Commercial mortgage loans, gross	$ 6,588	$ 0
Commercial mortgage loans, percent of total	25.40%	0.00%
Middle Atlantic
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Commercial mortgage loans, gross	$ 4,369	$ 0
Commercial mortgage loans, percent of total	16.90%	0.00%
LTV Less Than 65 Percent
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Commercial mortgage loans, gross	$ 25,828	$ 0

Percentage Of Commercial Mortgage Loans To Total Commercial Mortgage Loans

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- Definition

The reserve to cover probable credit losses related to specifically identified fixed maturity real estate loans as well as probable credit losses inherent in the remainder of that loan portfolio.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 310
-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=82921503&loc=d3e21338-158488

+ Details

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- Definition

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.

+ References

No definition available.

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- Definition

Amount before allowance of mortgage loans on existing land or building. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5066-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(a)(3))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Definition

The balance represents the amount of loans that are secured by real estate mortgages, offset by the reserve to cover probable credit losses on the loan portfolio.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.1(c))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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