HISTORICAL LOSS AND LAE DEVELOPMENT (Details 3) - 10K (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Unpaid losses and LAE at end of year:
Gross	$ 1,121,040	$ 1,129,433	$ 1,158,483	$ 1,150,714
Ceded	(335,106)	(354,924)	(359,884)	(353,805)
Net	785,934	774,509	798,599	796,909
Environmental, Asbestos and Mass Tort Claims
Loss and LAE payments (cumulative)
Gross	112,819	105,559	102,222
Ceded	(59,376)	(57,976)	(57,345)
Net	53,443	47,583	44,877
Unpaid losses and LAE at end of year:
Gross	39,064	48,507	50,353
Ceded	(11,879)	(15,043)	(16,733)
Net	$ 27,185	$ 33,464	$ 33,620
Minimum period for which product lines related to majority of reserves have been in runoff	20 years

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Represents the cumulative amount of recoveries to date from reinsurers for claims paid by the ceding insurer and associated claims settlement expenses.

+ References

No definition available.

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- Definition

Cumulative amount of payments made to date to settle insured claims and pay costs incurred in the claims settlement process, before recoveries from reinsurers.

+ References

No definition available.

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- Definition

Cumulative amount of payments made to date to settle insured claims and pay costs incurred in the claims settlement process, net of recoveries from reinsurers.

+ References

No definition available.

+ Details

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- Definition

Represents the minimum period for which the products lines associated with the majority of the reserves for environmental and asbestos claims have been in runoff.

+ References

No definition available.

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- Definition

The amount needed to reflect the estimated ultimate cost of settling claims relating to casualty insurance insured events that have occurred on or before a particular date (ordinarily, the balance sheet date) and the amount needed to provide for the estimated ultimate cost required to investigate and settle claims relating to insured events that have occurred on or before a particular date (ordinarily, the balance sheet date), whether or not reported to the insurer at that date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 18

-Article 12

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 40

-Section 50

-Paragraph 3

-Subparagraph (a),(b),(c)

-URI http://asc.fasb.org/extlink&oid=6482485&loc=d3e14764-158437

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- Definition

Liability as of the balance sheet date for amounts representing estimated cost of settling unpaid claims under the terms of the underlying insurance policies, less estimated reinsurance recoveries on such claims. This includes an estimate for claims which have been incurred but not reported. Claim adjustment expenses represent the costs estimated to be incurred in the settlement of unpaid claims.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 40

-Section 50

-Paragraph 3

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6482485&loc=d3e14764-158437

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Financial Reporting Release (FRR)

-Number 403

-Paragraph 04

-Subparagraph b

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 13

-Subparagraph a

-Article 7

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- Definition

Amount after valuation allowance recoverable under reinsurance contracts for claims and claims adjustments.

+ References

+ Details

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