Reinsurance (Details 3) (USD $) In Thousands	Jun. 30, 2011	Dec. 31, 2010
Amounts of letters of credit and cash deposits held by us as collateral, plus other credits available for potential offset
Payables to reinsurers	$ 266,374	$ 243,990
Letters of credit	137,859	145,914
Cash deposits	92,996	81,966
Total credits	$ 497,229	$ 471,870

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