INVESTMENTS (DETAILS 3) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014 security	Dec. 31, 2013 security
Fixed Maturities [Member]
Schedule Of Available For Sale Securities [Line Items]
Fair Value - 12 months or greater	$ 1,354,213	$ 271,520
Unrealized Losses - 12 months or greater	(71,302)	(13,466)
Fair Value - Less than 12 months	4,801,110	4,889,507
Unrealized Losses - Less than 12 months	(101,936)	(166,571)
Total Fair Value of Securities in Unrealized Loss Position	6,155,323	5,161,027
Total Unrealized Losses	(173,238)	(180,037)
Number of Available For Sale Securities In Unrealized Loss Positions	1,388	1,127
Number of Available For Sale Securities in Unrealized Loss Positions for 12 Months or Greater	223	99
Fixed Maturities [Member] \| Below Investment Grade or Not Rated [Member]
Schedule Of Available For Sale Securities [Line Items]
Total Unrealized Losses	(36,000)	(2,000)
US Government and Agency [Member]
Schedule Of Available For Sale Securities [Line Items]
Fair Value - 12 months or greater	388,551	0
Unrealized Losses - 12 months or greater	(24,319)	0
Fair Value - Less than 12 months	786,850	982,307
Unrealized Losses - Less than 12 months	(4,009)	(33,952)
Total Fair Value of Securities in Unrealized Loss Position	1,175,401	982,307
Total Unrealized Losses	(28,328)	(33,952)
Non-US Government [Member]
Schedule Of Available For Sale Securities [Line Items]
Fair Value - 12 months or greater	143,602	35,577
Unrealized Losses - 12 months or greater	(29,171)	(3,430)
Fair Value - Less than 12 months	435,670	420,622
Unrealized Losses - Less than 12 months	(25,270)	(46,562)
Total Fair Value of Securities in Unrealized Loss Position	579,272	456,199
Total Unrealized Losses	(54,441)	(49,992)
Corporate Debt [Member]
Schedule Of Available For Sale Securities [Line Items]
Fair Value - 12 months or greater	26,708	27,696
Unrealized Losses - 12 months or greater	(2,221)	(802)
Fair Value - Less than 12 months	2,199,672	606,592
Unrealized Losses - Less than 12 months	(64,059)	(9,426)
Total Fair Value of Securities in Unrealized Loss Position	2,226,380	634,288
Total Unrealized Losses	(66,280)	(10,228)
Agency RMBS [Member]
Schedule Of Available For Sale Securities [Line Items]
Fair Value - 12 months or greater	259,914	144,468
Unrealized Losses - 12 months or greater	(3,084)	(5,247)
Fair Value - Less than 12 months	333,288	1,478,527
Unrealized Losses - Less than 12 months	(1,151)	(53,044)
Total Fair Value of Securities in Unrealized Loss Position	593,202	1,622,995
Total Unrealized Losses	(4,235)	(58,291)
CMBS [Member]
Schedule Of Available For Sale Securities [Line Items]
Fair Value - 12 months or greater	68,624	13,319
Unrealized Losses - 12 months or greater	(925)	(116)
Fair Value - Less than 12 months	256,225	298,863
Unrealized Losses - Less than 12 months	(1,094)	(3,850)
Total Fair Value of Securities in Unrealized Loss Position	324,849	312,182
Total Unrealized Losses	(2,019)	(3,966)
Non-Agency RMBS [Member]
Schedule Of Available For Sale Securities [Line Items]
Fair Value - 12 months or greater	6,689	4,287
Unrealized Losses - 12 months or greater	(613)	(315)
Fair Value - Less than 12 months	13,442	5,319
Unrealized Losses - Less than 12 months	(302)	(83)
Total Fair Value of Securities in Unrealized Loss Position	20,131	9,606
Total Unrealized Losses	(915)	(398)
ABS [Member]
Schedule Of Available For Sale Securities [Line Items]
Fair Value - 12 months or greater	425,663	37,765
Unrealized Losses - 12 months or greater	(10,325)	(2,941)
Fair Value - Less than 12 months	750,679	553,803
Unrealized Losses - Less than 12 months	(5,863)	(5,753)
Total Fair Value of Securities in Unrealized Loss Position	1,176,342	591,568
Total Unrealized Losses	(16,188)	(8,694)
Municipals [Member]
Schedule Of Available For Sale Securities [Line Items]
Fair Value - 12 months or greater	34,462	8,408
Unrealized Losses - 12 months or greater	(644)	(615)
Fair Value - Less than 12 months	25,284	543,474
Unrealized Losses - Less than 12 months	(188)	(13,901)
Total Fair Value of Securities in Unrealized Loss Position	59,746	551,882
Total Unrealized Losses	(832)	(14,516)
Equity Securities [Member]
Schedule Of Available For Sale Securities [Line Items]
Fair Value - 12 months or greater	0	3,499
Unrealized Losses - 12 months or greater	0	(398)
Fair Value - Less than 12 months	204,092	48,828
Unrealized Losses - Less than 12 months	(7,524)	(5,785)
Total Fair Value of Securities in Unrealized Loss Position	204,092	52,327
Total Unrealized Losses	(7,524)	(6,183)
Number of Available For Sale Securities In Unrealized Loss Positions	9	63
Number of Available For Sale Securities in Unrealized Loss Positions for 12 Months or Greater	0	9
Common Stock [Member]
Schedule Of Available For Sale Securities [Line Items]
Fair Value - 12 months or greater	0	3,499
Unrealized Losses - 12 months or greater	0	(398)
Fair Value - Less than 12 months	0	48,828
Unrealized Losses - Less than 12 months	0	(5,785)
Total Fair Value of Securities in Unrealized Loss Position	0	52,327
Total Unrealized Losses	0	(6,183)
Exchange-Traded Funds [Member]
Schedule Of Available For Sale Securities [Line Items]
Fair Value - 12 months or greater	0	0
Unrealized Losses - 12 months or greater	0	0
Fair Value - Less than 12 months	91,275	0
Unrealized Losses - Less than 12 months	(4,756)	0
Total Fair Value of Securities in Unrealized Loss Position	91,275	0
Total Unrealized Losses	(4,756)	0
Non-U.S. Bond Mutual Funds [Member]
Schedule Of Available For Sale Securities [Line Items]
Fair Value - 12 months or greater	0	0
Unrealized Losses - 12 months or greater	0	0
Fair Value - Less than 12 months	112,817	0
Unrealized Losses - Less than 12 months	(2,768)	0
Total Fair Value of Securities in Unrealized Loss Position	112,817	0
Total Unrealized Losses	$ (2,768)	$ 0

Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for twelve months or longer.

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