Quarterly report pursuant to Section 13 or 15(d)

Securities - U.S. GSE, Agency, and Treasury Securities (Details)

v2.4.0.6
Securities - U.S. GSE, Agency, and Treasury Securities (Details) (USD $)
In Millions, unless otherwise specified
Mar. 31, 2012
Dec. 31, 2011
Schedule of Held-to-maturity Securities [Line Items]    
Held-to-maturity debt securities, Amortized Cost $ 34,205 [1] $ 35,265
Held-to-maturity Securities, Fair Value 34,440 35,442
Federal National Mortgage Association Certificates and Obligations (FNMA) [Member]
    
Schedule of Held-to-maturity Securities [Line Items]    
Held-to-maturity debt securities, Amortized Cost 111,297 87,898
Held-to-maturity Securities, Fair Value 111,915 89,243
Government National Mortgage Association Certificates and Obligations (GNMA) [Member]
    
Schedule of Held-to-maturity Securities [Line Items]    
Held-to-maturity debt securities, Amortized Cost 110,034 102,960
Held-to-maturity Securities, Fair Value 112,506 106,200
Federal Home Loan Mortgage Corporation Certificates and Obligations (FHLMC) [Member]
    
Schedule of Held-to-maturity Securities [Line Items]    
Held-to-maturity debt securities, Amortized Cost 26,656 26,617
Held-to-maturity Securities, Fair Value 26,979 27,129
United States Treasury Securities Exceeding Ten Percent Of Consolidated Shareholders Equity [Member]
    
Schedule of Held-to-maturity Securities [Line Items]    
Held-to-maturity debt securities, Amortized Cost 40,202 39,946
Held-to-maturity Securities, Fair Value $ 39,558 $ 39,164
[1] Substantially all U.S. agency mortgage-backed securities.