INVESTMENTS (Details 7) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Net Investment Income [Line Items]
Gross investment income	$ 102,278	$ 125,004	$ 321,031	$ 281,498
Investment expenses	(7,109)	(8,081)	(21,132)	(23,680)
Net investment income	95,169	116,923	299,899	257,818
Fixed Maturities [Member]
Net Investment Income [Line Items]
Gross investment income	74,978	75,827	230,603	229,423
Other Investments [Member]
Net Investment Income [Line Items]
Gross investment income	17,373	38,248	59,973	25,770
Equity Securities [Member]
Net Investment Income [Line Items]
Gross investment income	3,223	4,633	11,048	12,843
Mortgage loans [Member]
Net Investment Income [Line Items]
Gross investment income	2,895	2,191	7,970	5,683
Cash And Cash Equivalents [Member]
Net Investment Income [Line Items]
Gross investment income	3,111	3,768	9,640	7,071
Short-term Investments [Member]
Net Investment Income [Line Items]
Gross investment income	$ 698	$ 337	$ 1,797	$ 708

The net gain or loss (both realized and unrealized) related to investments in certain entities that calculate net asset value per share and the amount after accretion (amortization) of discount (premium), of interest income and dividend income on nonoperating securities.

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The net gain or loss (both realized and unrealized) related to investments in certain entities that calculate net asset value per share and the amount after accretion (amortization) of discount (premium) of interest income and dividend income on nonoperating securities, net of investment expense.

+ References

No definition available.

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Amount of expenses related to the generation of investment income.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.9)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04.2)
-URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913

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