v2.4.0.6
Cash, Loan and Dividend Restrictions (Details) (USD $)
In Billions, except Per Share data, unless otherwise specified
1 Months Ended 12 Months Ended
Jan. 22, 2013
Dec. 31, 2012
Dec. 31, 2011
Dec. 31, 2010
Cash, Loan and Dividend Restrictions [Line Items]        
Average required reserve balance on deposits   $ 9.1 $ 7.0  
Per share dividend amount requiring approval $ 0.25 $ 0.88 $ 0.48 $ 0.20
Total capital ratio required to be well capitalized   10.00%    
Credit And Non-Credit Transactions With All Nonbank Affiliates, Maximum Percent of Bank Capital and Surplus   20.00%    
Credit and non-credit transactions with a single nonbank affiliate, maximum percent of bank capital and surplus [Member] [Member]
       
Cash, Loan and Dividend Restrictions [Line Items]        
Total capital ratio required to be well capitalized   10.00%    
Nonbank Subsidiaries [Member]
       
Cash, Loan and Dividend Restrictions [Line Items]        
Additional dividends that could have been declared by national and state-chartered subsidiary bank/nonbank subsidiaries   6.2    
National And State Chartered Subsidiary Banks [Member]
       
Cash, Loan and Dividend Restrictions [Line Items]        
Additional dividends that could have been declared by national and state-chartered subsidiary bank/nonbank subsidiaries   $ 1.7