COMMITMENTS AND CONTINGENCIES (DETAILS 3) (USD $)	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
COMMITMENTS AND CONTINGENCIES [Abstract]
Rent expense related to operating leases	$ 24,000,000	$ 19,000,000	$ 17,000,000
Outstanding reinsurance purchase commitment	67,000,000
Office Space [Member]
Future minimum lease payments under operating leases [Line Items]
2012	21,872,000
2013	27,004,000
2014	28,373,000
2015	23,066,000
2016	19,664,000
Later years	82,373,000
Total minimum future lease commitments	$ 202,352,000

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- Definition

The total of future contractually required payments on leases defined as operating.

+ References

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 13

-Paragraph 122

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For leases having an initial or remaining non-cancelable letter-terms in excess of one year, required rental payments due within one year of the balance sheet date relating to leases defined as operating.

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For leases having an initial or remaining non-cancelable letter-terms in excess of one year, required rental payments due within the fifth year of the balance sheet date relating to leases defined as operating.

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For leases having an initial or remaining non-cancelable letter-terms in excess of one year, required rental payments due within the fourth year of the balance sheet date relating to leases defined as operating.

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For leases having an initial or remaining non-cancelable letter-terms in excess of one year, required rental payments due within the third year of the balance sheet date relating to leases defined as operating.

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For leases having an initial or remaining non-cancelable letter-terms in excess of one year, required rental payments due within the second year of the balance sheet date relating to leases defined as operating.

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For leases having an initial or remaining non-cancelable letter-terms in excess of one year, required rental payments due after the fifth year from the balance sheet date on leases defined as operating.

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- Definition

Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income.

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The floor amount as of the balance sheet date that the entity must expend to satisfy the terms of disclosed arrangements (excluding long-term commitments) in which the entity has agreed to expend funds to procure goods or services from one or more suppliers, other than under a long-term purchase commitment or an unconditional purchase obligation.

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