Reinsurance (Details 4) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Amounts of letters of credit and cash available to us as collateral, plus other potential offsets
Payables to reinsurers	$ 208,483	$ 190,228
Letters of credit	87,033	89,832
Cash	89,469	116,597
Total credits	$ 384,985	$ 396,657