v2.3.0.15
Investments (Schedule Of Fair Value Of Fixed Maturity Investments) (Details) (USD $)
In Thousands
Sep. 30, 2011
Dec. 31, 2010
Fixed maturity investments trading, fair value$ 3,687,669$ 3,871,780
U.S. Treasuries [Member]
  
Fixed maturity investments trading, fair value428,865761,461
Agencies [Member]
  
Fixed maturity investments trading, fair value127,063216,963
Non-U.S. Government (Sovereign Debt) [Member]
  
Fixed maturity investments trading, fair value390,637157,867
FDIC Guaranteed Corporate [Member]
  
Fixed maturity investments trading, fair value183,314388,468
Non-U.S. Government-Backed Corporate [Member]
  
Fixed maturity investments trading, fair value594,573356,119
Corporate [Member]
  
Fixed maturity investments trading, fair value1,273,4321,476,029
Agency Mortgage-Backed [Member]
  
Fixed maturity investments trading, fair value347,387383,403
Non-Agency Mortgage-Backed [Member]
  
Fixed maturity investments trading, fair value80,5035,765
Commercial Mortgage-Backed [Member]
  
Fixed maturity investments trading, fair value247,509125,705
Asset-Backed [Member]
  
Fixed maturity investments trading, fair value$ 14,386