MORTGAGE LOANS - Troubled Debt Restructuring (Details) - Commercial mortgage loans $ in Thousands	12 Months Ended
Dec. 31, 2017 USD ($) contract
Troubled debt restructuring:
Number of Contracts \| contract	1
Pre-Modification Outstanding Recorded Investment	$ 418
Post-Modification Outstanding Recorded Investment	$ 418

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Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524

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Post-modification amount of investment in financing receivables modified by troubled debt restructurings.

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Pre-modification amount of investment in financing receivables modified by troubled debt restructurings.

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