FAIR VALUE MEASUREMENTS (DETAILS 3) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Fixed Maturities [Member]
Changes in Level 3 Financial Instruments Measured at Fair Value on a Recurring Basis [Line Items]
Balance at beginning of period	$ 73,631	$ 34,817
Transfers into Level 3	0	128
Transfers out of Level 3	0	0
Included in earnings	0	0
Included in OCI	38	(115)
Purchases	10,910	0
Sales	0	0
Settlements/ Distributions	(740)	(137)
Balance at end of period	83,839	34,693
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]
Balance at beginning of period	617,844	557,055
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Included in earnings	25,685	14,879
Included in OCI	0	0
Purchases	21,418	20,790
Sales	0	0
Settlements/ Distributions	(7,358)	(15,876)
Balance at end of period	657,589	576,848
Change in unrealized investment gain/loss relating to assets held at the reporting date	25,685	14,879
Other Assets [Member]
Changes in Level 3 Financial Instruments Measured at Fair Value on a Recurring Basis [Line Items]
Balance at beginning of period	111	984
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Included in earnings	(1,067)	4,718
Included in OCI	0	0
Purchases	25,000	0
Sales	0	0
Settlements/ Distributions	956	(3,995)
Balance at end of period	25,000	1,707
Change in unrealized investment gain/loss relating to assets held at the reporting date	0	1,540
Total Assets [Member]
Changes in Level 3 Financial Instruments Measured at Fair Value on a Recurring Basis [Line Items]
Balance at beginning of period	691,586	592,856
Transfers into Level 3	0	128
Transfers out of Level 3	0	0
Included in earnings	24,618	19,597
Included in OCI	38	(115)
Purchases	57,328	20,790
Sales	0	0
Settlements/ Distributions	(7,142)	(20,008)
Balance at end of period	766,428	613,248
Change in unrealized investment gain/loss relating to assets held at the reporting date	25,685	16,419
Total Liabilities [Member]
Changes in Level 3 Financial Instruments Measured at Fair Value on a Recurring Basis [Line Items]
Balance at beginning of period	15,288	815
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Included in earnings	(8,551)	986
Included in OCI	0	0
Purchases	1,082	0
Sales	0	0
Settlements/ Distributions	(511)	(1,801)
Balance at end of period	7,308	0
Change in unrealized investment gain/loss relating to assets held at the reporting date	(2,058)	0
Corporate Debt [Member] \| Fixed Maturities [Member]
Changes in Level 3 Financial Instruments Measured at Fair Value on a Recurring Basis [Line Items]
Balance at beginning of period	15,837	0
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Included in earnings	0	0
Included in OCI	180	0
Purchases	10,910	0
Sales	0	0
Settlements/ Distributions	(70)	0
Balance at end of period	26,857	0
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]
Balance at beginning of period	17,763	4,018
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Included in earnings	0	0
Included in OCI	(204)	(20)
Purchases	0	0
Sales	0	0
Settlements/ Distributions	(498)	(29)
Balance at end of period	17,061	3,969
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]
Balance at beginning of period	40,031	30,799
Transfers into Level 3	0	128
Transfers out of Level 3	0	0
Included in earnings	0	0
Included in OCI	62	(95)
Purchases	0	0
Sales	0	0
Settlements/ Distributions	(172)	(108)
Balance at end of period	39,921	30,724
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]
Balance at beginning of period	470,918	461,055
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Included in earnings	18,931	8,177
Included in OCI	0	0
Purchases	6,000	4,500
Sales	0	0
Settlements/ Distributions	0	(9,066)
Balance at end of period	495,849	464,666
Change in unrealized investment gain/loss relating to assets held at the reporting date	18,931	8,177
Direct Lending Funds [Member] \| Other Investments [Member]
Changes in Level 3 Financial Instruments Measured at Fair Value on a Recurring Basis [Line Items]
Balance at beginning of period	54,438	22,134
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Included in earnings	667	552
Included in OCI	0	0
Purchases	15,418	3,445
Sales	0	0
Settlements/ Distributions	(841)	(128)
Balance at end of period	69,682	26,003
Change in unrealized investment gain/loss relating to assets held at the reporting date	667	552
CLO-Equities [Member] \| Other Investments [Member]
Changes in Level 3 Financial Instruments Measured at Fair Value on a Recurring Basis [Line Items]
Balance at beginning of period	92,488	73,866
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Included in earnings	6,087	6,150
Included in OCI	0	0
Purchases	0	12,845
Sales	0	0
Settlements/ Distributions	(6,517)	(6,682)
Balance at end of period	92,058	86,179
Change in unrealized investment gain/loss relating to assets held at the reporting date	6,087	6,150
Derivative [Member] \| Other Assets [Member]
Changes in Level 3 Financial Instruments Measured at Fair Value on a Recurring Basis [Line Items]
Balance at beginning of period	111	984
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Included in earnings	(1,067)	4,718
Included in OCI	0	0
Purchases	0	0
Sales	0	0
Settlements/ Distributions	956	(3,995)
Balance at end of period	0	1,707
Change in unrealized investment gain/loss relating to assets held at the reporting date	0	1,540
Derivative [Member] \| Other Liabilities [Member]
Changes in Level 3 Financial Instruments Measured at Fair Value on a Recurring Basis [Line Items]
Balance at beginning of period	15,288	815
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Included in earnings	(8,551)	986
Included in OCI	0	0
Purchases	1,082	0
Sales	0	0
Settlements/ Distributions	(511)	(1,801)
Balance at end of period	7,308	0
Change in unrealized investment gain/loss relating to assets held at the reporting date	(2,058)	0
Insurance-linked securities [Member] \| Other Assets [Member]
Changes in Level 3 Financial Instruments Measured at Fair Value on a Recurring Basis [Line Items]
Balance at beginning of period	0	0
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Included in earnings	0	0
Included in OCI	0	0
Purchases	25,000	0
Sales	0	0
Settlements/ Distributions	0	0
Balance at end of period	25,000	0
Change in unrealized investment gain/loss relating to assets held at the reporting date	$ 0	$ 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

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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 transfer of financial instrument classified as an asset into level 3 of the fair value hierarchy.

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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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