INVESTMENT OPERATIONS - Schedule of Other-than-Temporary Impairments of Investments (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Investment [Line Items]
Other-than-temporary impairment losses	$ (10)	$ (33)	$ (701)	$ (2,758)
Portion recognized in other comprehensive income (before taxes)	5	(2,752)	(2,949)	(7,858)
Net impairment losses recognized in earnings	(5)	(2,785)	(3,650)	(10,616)
Fixed maturities
Investment [Line Items]
Other-than-temporary impairment losses	(10)	(33)	(701)	(128)
Portion recognized in other comprehensive income (before taxes)	5	(2,752)	(2,949)	(7,858)
Net impairment losses recognized in earnings	$ (5)	(2,785)	$ (3,650)	(7,986)
Equity securities
Investment [Line Items]
Other-than-temporary impairment losses		0		(2,630)
Portion recognized in other comprehensive income (before taxes)		0		0
Net impairment losses recognized in earnings		$ 0		$ (2,630)

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- Definition

Noncredit portion of impairment gains (losses) on investments reclassified to other comprehensive income for those securities that meet the criteria to have impairment losses bifurcated between net income (credit losses) and other comprehensive income (noncredit losses).

+ References

No definition available.

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- Definition

This element represents the amount of loss recognized for other than temporary impairments (OTTI) of investments in debt and equity securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 5.M)
-URI http://asc.fasb.org/extlink&oid=65877573&loc=d3e87990-122713

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- Definition

The amount of other than temporary impairment (OTTI) losses on equity securities, OTTI related to credit losses on debt securities, and OTTI losses on debt securities when the entity intends to sell the securities or it is more likely than not that the entity will be required to sell the securities before recovery of its amortized cost basis. Additionally, this item includes OTTI losses recognized during the period on investments accounted for under the cost method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 8B
-URI http://asc.fasb.org/extlink&oid=82897076&loc=SL6284393-111563

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