v2.4.0.6
Available-For-Sale Securities (Summary Of Available-For-Sale Debt Securities By Contractual Maturity) (Details) (USD $)
In Thousands, unless otherwise specified
Dec. 31, 2011
Dec. 31, 2010
Available-For-Sale Securities [Abstract]    
Less than one year, Amortized Cost $ 1,574,140 $ 1,726,095
Greater than one year but less than five years, Amortized Cost 26,100 3,022,744
Greater than five years but less than ten years, Amortized Cost 0 33,076
Greater than ten years, Amortized Cost 7,507,482 142,338
Total, Amortized Cost 9,107,722 4,924,253
Less than one year, Fair Value 1,561,462 1,729,735
Greater than one year but less than five years, Fair Value 8,249 3,044,114
Greater than five years but less than ten years, Fair Value 0 33,580
Greater than ten years, Fair Value 7,502,935 137,078
Total, Fair Value $ 9,072,646 $ 4,944,507