v3.3.1.900
Schedule I Summary of Investments, Other than Investments in Related Parties (Details) - USD ($)
$ in Thousands
Dec. 31, 2015
Dec. 31, 2014
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]    
Amortized Cost $ 3,562,864 $ 3,379,864
HTM securities, Amortized Cost 607,843 0
Other Investments, Amortized Cost 10,816 10,862
Total investments, Original or Amortized cost 4,181,523 3,390,726
Fair value 3,508,088 3,456,904
HTM securities, Fair Value 598,975 0
Other investments 11,812 12,571
Total investments, Fair value 4,118,875 3,469,475
Amount at Which Shown in the Balance Sheet 4,127,743  
U.S. treasury bonds    
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]    
Amortized Cost 5,714 8,937
Fair value 6,010 9,360
Amount at Which Shown in the Balance Sheet 6,010  
U.S. agency bonds – mortgage-backed    
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]    
Amortized Cost 1,471,782 1,313,834
Fair value 1,476,991 1,322,443
Amount at Which Shown in the Balance Sheet 1,476,991  
U.S. agency bonds – other    
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]    
Amortized Cost 23,734 7,213
Fair value 24,311 7,988
Amount at Which Shown in the Balance Sheet 24,311  
Non-U.S. government and supranational bonds    
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]    
Amortized Cost 35,128 54,467
Fair value 30,544 51,643
Amount at Which Shown in the Balance Sheet 30,544  
Asset-backed securities    
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]    
Amortized Cost 165,719  
Fair value 165,804  
Amount at Which Shown in the Balance Sheet 165,804  
Corporate bonds    
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]    
Amortized Cost 1,798,610 1,831,431
HTM securities, Amortized Cost 607,843  
Fair value 1,739,668 $ 1,895,379
HTM securities, Fair Value 598,975  
Amount at Which Shown in the Balance Sheet 1,739,668  
Municipal bonds    
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]    
Amortized Cost 62,177  
Fair value 64,760  
Amount at Which Shown in the Balance Sheet 64,760  
Total AFS fixed maturities    
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]    
Amortized Cost 3,562,864  
Fair value 3,508,088  
Amount at Which Shown in the Balance Sheet 3,508,088  
HTM Corporate bonds    
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]    
HTM securities, Amortized Cost 607,843  
HTM securities, Fair Value 598,975  
Amount at Which Shown in the Balance Sheet 607,843  
HTM fixed maturities    
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]    
HTM securities, Amortized Cost 607,843  
HTM securities, Fair Value 598,975  
Amount at Which Shown in the Balance Sheet 607,843  
Other investments    
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]    
Other Investments, Amortized Cost 10,816  
Other investments 11,812  
Amount at Which Shown in the Balance Sheet $ 11,812