INVESTMENT OPERATIONS - Schedule of Gross Realized Gains (Losses) on Investments Available-for-Sale (Details) - USD ($) $ in Thousands	1 Months Ended	11 Months Ended	12 Months Ended
Jan. 31, 2015	Dec. 31, 2015	Dec. 31, 2017	Dec. 31, 2016
Investment [Line Items]
Gross realized gains		$ 8,745	$ 18,868	$ 42,085
Impairments losses		(26,993)	(11,742)	(17,748)
Other realized losses		$ (8,463)	$ (8,257)	$ (9,783)
Predecessor
Investment [Line Items]
Gross realized gains	$ 6,920
Impairments losses	(481)
Other realized losses	$ 12

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- Definition

Available-for-sale Securities, Other Gross Realized Gain (Loss)

+ References

No definition available.

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- Definition

This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27357-111563

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- Definition

The amount of other than temporary impairment losses on investments in debt and equity securities categorized as Available-for-sale which have been recognized in earnings during the period. Such impairment losses consist of other than temporary impairments (OTTI) on equity securities, credit losses on investments in debt securities, and when the entity intends to sell an impaired debt security or it is more likely than not that the entity will be required to sell the impaired debt security before recovery of its amortized cost basis.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 8A
-URI http://asc.fasb.org/extlink&oid=82896770&loc=SL6284422-111562

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