v2.4.0.6
Variable Interest Entities (Details) (USD $)
3 Months Ended 6 Months Ended 1 Months Ended 6 Months Ended 1 Months Ended
Jun. 30, 2012
Jun. 30, 2011
Jun. 30, 2012
Jun. 30, 2011
Jun. 30, 2012
Upsilon Re [Member]
Variable Interest Entity, Primary Beneficiary [Member]
Jun. 30, 2012
Tim Re III [Member]
Variable Interest Entity, Primary Beneficiary [Member]
Jun. 30, 2012
Nonvoting Class B Shares [Member]
Upsilon Re [Member]
Variable Interest Entity, Primary Beneficiary [Member]
Jun. 30, 2012
Nonvoting Class B Shares [Member]
Tim Re III [Member]
Variable Interest Entity, Primary Beneficiary [Member]
Variable Interest Entity [Line Items]                
Gross premiums written $ 667,336,000 $ 641,563,000 $ 1,331,487,000 $ 1,252,068,000 $ 37,400,000 $ 41,100,000    
Ceded premiums written 239,706,000 213,568,000 411,282,000 371,498,000   37,700,000    
Issuance of equity to third party investors             16,800,000 44,800,000
Additional contribution               10,300,000
Variable interest entity, ownership percentage         74.50% 18.60%    
Investment in variable interest entity             48,800,000  
Risk participation percentage         61.40%      
Capital provided in connection with third party reinsurance participation         $ 17,600,000 $ 5,200,000