SEGMENT INFORMATION (DETAILS) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015 reportable_segment	Mar. 31, 2014	Dec. 31, 2014
Segment Information [Line Items]
Number of reportable segments	2us-gaap_NumberOfReportableSegments
Net premiums earned	$ 906,222us-gaap_PremiumsEarnedNet	$ 945,949us-gaap_PremiumsEarnedNet
Other insurance related income	7,676us-gaap_OtherOperatingIncome	3,082us-gaap_OtherOperatingIncome
Net losses and loss expenses	(518,937)	(544,207)
Acquisition costs	(171,702)	(172,036)
General and administrative expenses	(163,517)	(152,729)
Net investment income	92,110	82,744
Net realized investment gains (losses)	(42,553)	10,620
Foreign exchange (losses) gains	63,220	(4,233)
Interest expense and financing costs	(12,257)us-gaap_InterestExpense	(16,594)us-gaap_InterestExpense
Income before income taxes	160,262	152,596
Net loss and loss expense ratio	57.30%us-gaap_LossRatio	57.50%us-gaap_LossRatio
Acquisition cost ratio	18.90%us-gaap_AcquisitionCostRatio	18.20%us-gaap_AcquisitionCostRatio
General and administrative expense ratio	18.10%	16.20%
Combined ratio	94.30%us-gaap_CombinedRatio	91.90%us-gaap_CombinedRatio
Goodwill and intangible assets	88,508	90,350	88,960
Operating Segments [Member]
Segment Information [Line Items]
Gross premiums written	1,678,932	1,821,399
Net premiums written	1,463,552	1,664,584
Net premiums earned	906,222	945,949
Other insurance related income	7,676	3,082
Net losses and loss expenses	(518,937)	(544,207)
Acquisition costs	(171,702)	(172,036)
General and administrative expenses	(127,345)	(124,022)
Underwriting income	95,914	108,766
Operating Segments [Member] \| Insurance [Member]
Segment Information [Line Items]
Gross premiums written	602,724	601,721
Net premiums written	436,740	456,692
Net premiums earned	447,467	449,214
Other insurance related income	0	0
Net losses and loss expenses	(285,773)	(279,423)
Acquisition costs	(64,455)	(65,057)
General and administrative expenses	(87,689)	(87,946)
Underwriting income	9,550	16,788
Net loss and loss expense ratio	63.90%	62.20%
Acquisition cost ratio	14.40%	14.50%
General and administrative expense ratio	19.60%	19.60%
Combined ratio	97.90%	96.30%
Goodwill and intangible assets	88,508	90,350
Operating Segments [Member] \| Reinsurance [Member]
Segment Information [Line Items]
Gross premiums written	1,076,208	1,219,678
Net premiums written	1,026,812	1,207,892
Net premiums earned	458,755	496,735
Other insurance related income	7,676	3,082
Net losses and loss expenses	(233,164)	(264,784)
Acquisition costs	(107,247)	(106,979)
General and administrative expenses	(39,656)	(36,076)
Underwriting income	86,364	91,978
Net loss and loss expense ratio	50.80%	53.30%
Acquisition cost ratio	23.40%	21.50%
General and administrative expense ratio	8.60%	7.30%
Combined ratio	82.80%	82.10%
Goodwill and intangible assets	0	0
Corporate, Non-Segment [Member]
Segment Information [Line Items]
General and administrative expenses	(36,172)	(28,707)
Significant Reconciling Items [Member]
Segment Information [Line Items]
Net investment income	92,110	82,744
Net realized investment gains (losses)	(42,553)	10,620
Foreign exchange (losses) gains	63,220	(4,233)
Interest expense and financing costs	$ (12,257)	$ (16,594)

This item represents the difference between the gross realized gains and losses realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. Additionally, this item would include any losses recognized for other than temporary impairments (OTTI) of the subject investments in debt and equity securities, the change in fair value of investment-related derivatives not designated as hedges and any hedge ineffectiveness recognized in earnings in relation to investment portfolio-related fair value hedges.

No definition available.