v2.4.0.6
Short-term Borrowings (Details) (USD $)
12 Months Ended
Dec. 31, 2012
Dec. 31, 2011
Dec. 31, 2010
Short-term Debt [Abstract]      
Short-term borrowings, Amount $ 57,175,000,000 $ 49,091,000,000 $ 55,401,000,000
Short Term Borrowings, Rate 0.17% 0.10% 0.19%
Short term Debt average daily balance, Amount 51,196,000,000 51,781,000,000 46,824,000,000
Short term Debt average daily balance, Rate 0.18% 0.18% 0.22%
Federal Funds Purchased and Securities Sold under Agreements to Repurchase [Member]
     
Short-term Debt [Abstract]      
Short-term borrowings, Amount 34,973,000,000 31,038,000,000 37,947,000,000
Short Term Borrowings, Rate 0.17% 0.05% 0.15%
Short term Debt average daily balance, Amount 32,092,000,000 34,388,000,000 30,494,000,000
Short term Debt average daily balance, Rate 0.12% 0.11% 0.18%
Maximum month-end balance, Amount 36,327,000,000 37,509,000,000 37,947,000,000
Commercial paper and other short term borrowings [Member]
     
Short-term Debt [Abstract]      
Short-term borrowings, Amount 22,202,000,000 18,053,000,000 17,454,000,000
Short Term Borrowings, Rate 0.18% 0.19% 0.26%
Short term Debt average daily balance, Amount 19,104,000,000 17,393,000,000 16,330,000,000
Short term Debt average daily balance, Rate 0.28% 0.33% 0.31%
Maximum month-end balance, Amount $ 22,202,000,000 $ 18,234,000,000 $ 17,646,000,000