RELATED PARTY TRANSACTIONS (Detail) (USD $)	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Number Of Minority Owned Investment Management Company Affiliates	3	4
Premiums Written, Net	$ 5,795,750,000	$ 5,381,663,000	$ 5,276,564,000
Reserve for Losses and Loss Adjustment Expenses			1,200,000
Reinsurance Costs and Recoveries, Net			1,400,000
Reinsurance Contracts, ITAU XL Seguros Corporativoes S.A.
Premiums Written, Net			$ 3,100,000