FAIR VALUE MEASUREMENTS (DETAILS 3) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014
Fixed Maturities [Member]
Changes in Level 3 Financial Instruments Measured at Fair Value on a Recurring Basis [Line Items]
Opening Balance	$ 73,631	$ 34,817
Transfers into Level 3	5,072	10,572
Transfers out of Level 3	(57,756)	(6,165)
Included in earnings	(49)	0
Included in OCI	(457)	3,636
Purchases	39,225	60,784
Sales	(1,723)	0
Settlements/ Distributions	(8,503)	(30,013)
Closing Balance	49,440	73,631
Change in unrealized investment gain/(loss) relating to assets held at the reporting date	0	0
Other Investments [Member]
Changes in Level 3 Financial Instruments Measured at Fair Value on a Recurring Basis [Line Items]
Opening Balance	617,844	557,055
Transfers into Level 3	0	12,355
Transfers out of Level 3	(23,813)	(32,255)
Included in earnings	18,211	48,478
Included in OCI	0	0
Purchases	83,564	75,542
Sales	0	0
Settlements/ Distributions	(60,682)	(43,331)
Closing Balance	635,124	617,844
Change in unrealized investment gain/(loss) relating to assets held at the reporting date	11,971	48,339
Other Assets [Member]
Changes in Level 3 Financial Instruments Measured at Fair Value on a Recurring Basis [Line Items]
Opening Balance	111	984
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Included in earnings	2,480	5,112
Included in OCI	0	0
Purchases	26,865	0
Sales	0	0
Settlements/ Distributions	(136)	(5,985)
Closing Balance	29,320	111
Change in unrealized investment gain/(loss) relating to assets held at the reporting date	3,505	101
Total Assets [Member]
Changes in Level 3 Financial Instruments Measured at Fair Value on a Recurring Basis [Line Items]
Opening Balance	691,586	592,856
Transfers into Level 3	5,072	22,927
Transfers out of Level 3	(81,569)	(38,420)
Included in earnings	20,642	53,590
Included in OCI	(457)	3,636
Purchases	149,654	136,326
Sales	(1,723)	0
Settlements/ Distributions	(69,321)	(79,329)
Closing Balance	713,884	691,586
Change in unrealized investment gain/(loss) relating to assets held at the reporting date	15,476	48,440
Total Liabilities [Member]
Changes in Level 3 Financial Instruments Measured at Fair Value on a Recurring Basis [Line Items]
Opening Balance	15,288	815
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Included in earnings	(3,208)	10,604
Included in OCI	0	0
Purchases	4,795	12,715
Sales	0	0
Settlements/ Distributions	(5,938)	(8,846)
Closing Balance	10,937	15,288
Change in unrealized investment gain/(loss) relating to assets held at the reporting date	8,337	6,621
Corporate Debt [Member] \| Fixed Maturities [Member]
Changes in Level 3 Financial Instruments Measured at Fair Value on a Recurring Basis [Line Items]
Opening Balance	15,837	0
Transfers into Level 3	0	0
Transfers out of Level 3	(7,903)	0
Included in earnings	(49)	0
Included in OCI	88	(95)
Purchases	39,225	15,957
Sales	(1,723)	0
Settlements/ Distributions	(6,957)	(25)
Closing Balance	38,518	15,837
Change in unrealized investment gain/(loss) relating to assets held at the reporting date	0	0
CMBS [Member] \| Fixed Maturities [Member]
Changes in Level 3 Financial Instruments Measured at Fair Value on a Recurring Basis [Line Items]
Opening Balance	17,763	4,018
Transfers into Level 3	5,072	9,447
Transfers out of Level 3	(9,902)	0
Included in earnings	0	0
Included in OCI	(647)	1,381
Purchases	0	5,027
Sales	0	0
Settlements/ Distributions	(1,364)	(2,110)
Closing Balance	10,922	17,763
Change in unrealized investment gain/(loss) relating to assets held at the reporting date	0	0
ABS [Member] \| Fixed Maturities [Member]
Changes in Level 3 Financial Instruments Measured at Fair Value on a Recurring Basis [Line Items]
Opening Balance	40,031	30,799
Transfers into Level 3	0	1,125
Transfers out of Level 3	(39,951)	(6,165)
Included in earnings	0	0
Included in OCI	102	2,350
Purchases	0	39,800
Sales	0	0
Settlements/ Distributions	(182)	(27,878)
Closing Balance	0	40,031
Change in unrealized investment gain/(loss) relating to assets held at the reporting date	0	0
Hedge funds [Member] \| Other Investments [Member]
Changes in Level 3 Financial Instruments Measured at Fair Value on a Recurring Basis [Line Items]
Opening Balance	470,918	461,055
Transfers into Level 3	0	12,355
Transfers out of Level 3	(23,813)	(32,255)
Included in earnings	16,013	24,790
Included in OCI	0	0
Purchases	42,500	19,500
Sales	0	0
Settlements/ Distributions	(30,477)	(14,527)
Closing Balance	475,141	470,918
Change in unrealized investment gain/(loss) relating to assets held at the reporting date	9,773	24,651
Direct Lending Funds [Member] \| Other Investments [Member]
Changes in Level 3 Financial Instruments Measured at Fair Value on a Recurring Basis [Line Items]
Opening Balance	54,438	22,134
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Included in earnings	4,509	3,515
Included in OCI	0	0
Purchases	35,564	30,101
Sales	0	0
Settlements/ Distributions	(4,391)	(1,312)
Closing Balance	90,120	54,438
Change in unrealized investment gain/(loss) relating to assets held at the reporting date	4,509	3,515
Real Estate Funds [Member] \| Other Investments [Member]
Changes in Level 3 Financial Instruments Measured at Fair Value on a Recurring Basis [Line Items]
Opening Balance	0	0
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Included in earnings	(571)	0
Included in OCI	0	0
Purchases	5,500	0
Sales	0	0
Settlements/ Distributions	0	0
Closing Balance	4,929	0
Change in unrealized investment gain/(loss) relating to assets held at the reporting date	(571)	0
CLO-Equities [Member] \| Other Investments [Member]
Changes in Level 3 Financial Instruments Measured at Fair Value on a Recurring Basis [Line Items]
Opening Balance	92,488	73,866
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Included in earnings	(1,740)	20,173
Included in OCI	0	0
Purchases	0	25,941
Sales	0	0
Settlements/ Distributions	(25,814)	(27,492)
Closing Balance	64,934	92,488
Change in unrealized investment gain/(loss) relating to assets held at the reporting date	(1,740)	20,173
Derivative [Member] \| Other Assets [Member]
Changes in Level 3 Financial Instruments Measured at Fair Value on a Recurring Basis [Line Items]
Opening Balance	111	984
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Included in earnings	2,555	5,112
Included in OCI	0	0
Purchases	1,865	0
Sales	0	0
Settlements/ Distributions	(136)	(5,985)
Closing Balance	4,395	111
Change in unrealized investment gain/(loss) relating to assets held at the reporting date	3,580	101
Derivative [Member] \| Other Liabilities [Member]
Changes in Level 3 Financial Instruments Measured at Fair Value on a Recurring Basis [Line Items]
Opening Balance	15,288	815
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Included in earnings	(3,208)	10,604
Included in OCI	0	0
Purchases	4,795	12,715
Sales	0	0
Settlements/ Distributions	(5,938)	(8,846)
Closing Balance	10,937	15,288
Change in unrealized investment gain/(loss) relating to assets held at the reporting date	8,337	6,621
Insurance-linked Securities [Member] \| Other Assets [Member]
Changes in Level 3 Financial Instruments Measured at Fair Value on a Recurring Basis [Line Items]
Opening Balance	0	0
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Included in earnings	(75)	0
Included in OCI	0	0
Purchases	25,000	0
Sales	0	0
Settlements/ Distributions	0	0
Closing Balance	24,925	0
Change in unrealized investment gain/(loss) relating to assets held at the reporting date	$ (75)	$ 0

Amount of unrealized (holding) gain (loss) which is included in the statement of income (or changes in net assets) related to those assets still held at the reporting date for which fair value is measured on a recurring basis using significant unobservable inputs (Level 3).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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Amount of gain (loss) recognized in the income statement for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of gain (loss) recognized in other comprehensive income (loss) for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of sale of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of settlement of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of transfers of financial instrument classified as an asset out of level 3 of the fair value hierarchy.

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Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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