v2.4.0.6
Fair Value Measurements (Schedule Of Assets And Liabilities At Fair Value Measured On A Recurring Basis And Non-Recurring Basis) (Detail) (USD $)
Jun. 30, 2012
Mar. 31, 2012
Dec. 31, 2011
Jun. 30, 2011
Mar. 31, 2011
Dec. 31, 2010
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Securities available for sale $ 27,232,000,000   $ 24,471,000,000      
Mortgage loans held for sale 950,000,000   844,000,000      
Mortgage servicing rights 179,000,000 199,000,000 182,000,000 268,000,000 282,000,000 267,000,000
Loans held for sale 950,000,000   844,000,000      
Trading account assets, equity securities     178,000,000      
Federal Reserve Bank Stock excluded from fair value measurement 480,000,000   481,000,000      
Federal Home Loan Bank Stock excluded from fair value measurement 135,000,000   219,000,000      
Legally enforceable master netting agreements 1,200,000,000   1,400,000,000      
Cash collateral received, excluded from derivative instruments 57,000,000   55,000,000      
Cash collateral posted, excluded from derivative instruments 881,000,000   732,000,000      
Interest rate swaps included in derivative assets and derivative liabilities 0          
Interest rate options included in derivative assets and derivative liabilities 0          
Interest rate swaps included in derivative assets     454,000,000      
Interest rate options included in derivative assets     23,000,000      
U.S. Treasury Securities [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Securities available for sale 51,000,000   98,000,000      
Obligations Of States And Political Subdivisions [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Securities available for sale 14,000,000   36,000,000      
Residential Agency [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Securities available for sale 23,494,000,000   22,175,000,000      
Commercial Agency [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Securities available for sale 514,000,000   326,000,000      
Equity Securities [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Securities available for sale 722,000,000   815,000,000      
Federal Agency Securities [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Securities available for sale 235,000,000   147,000,000      
Residential Non-Agency [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Securities available for sale 14,000,000   16,000,000      
Commercial Non-Agency [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Securities available for sale 637,000,000   321,000,000      
Corporate And Other Debt Securities [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Securities available for sale 1,551,000,000   537,000,000      
Fair Value Inputs Level 1 [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Trading account assets 110,000,000          
Securities available for sale 158,000,000          
Fair Value Inputs Level 1 [Member] | Recurring Fair Value Measurements [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Trading account assets 110,000,000 [1]   577,000,000 [1]      
Securities available for sale 158,000,000   213,000,000      
Total trading account liabilities     1,000,000 [2]      
Fair Value Inputs Level 1 [Member] | Recurring Fair Value Measurements [Member] | U.S. Treasury Securities [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Trading account assets     212,000,000      
Securities available for sale 51,000,000   98,000,000      
Fair Value Inputs Level 1 [Member] | Recurring Fair Value Measurements [Member] | Equity Securities [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Trading account assets 110,000,000   365,000,000      
Securities available for sale 107,000,000 [3]   115,000,000 [3]      
Total trading account liabilities     1,000,000      
Fair Value Inputs Level 2 [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Securities available for sale 27,058,000,000          
Total derivative liabilities 2,025,000,000 [4],[5]   2,514,000,000 [4],[5]      
Loans held for sale 981,000,000          
Fair Value Inputs Level 2 [Member] | Recurring Fair Value Measurements [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Trading account assets     498,000,000 [1]      
Securities available for sale 26,443,000,000   23,522,000,000      
Mortgage loans held for sale 950,000,000   844,000,000      
Total derivative assets 2,119,000,000 [4],[5]   2,840,000,000 [4],[5]      
Total trading account liabilities     248,000,000 [2]      
Fair Value Inputs Level 2 [Member] | Recurring Fair Value Measurements [Member] | U.S. Treasury Securities [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Trading account assets     3,000,000      
Total trading account liabilities     97,000,000      
Fair Value Inputs Level 2 [Member] | Recurring Fair Value Measurements [Member] | Obligations Of States And Political Subdivisions [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Trading account assets     101,000,000      
Securities available for sale 14,000,000   16,000,000      
Total trading account liabilities     2,000,000      
Fair Value Inputs Level 2 [Member] | Recurring Fair Value Measurements [Member] | Residential Agency [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Trading account assets     359,000,000      
Securities available for sale 23,494,000,000   22,175,000,000      
Total trading account liabilities     133,000,000      
Fair Value Inputs Level 2 [Member] | Recurring Fair Value Measurements [Member] | Commercial Agency [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Securities available for sale 514,000,000   326,000,000      
Fair Value Inputs Level 2 [Member] | Recurring Fair Value Measurements [Member] | Other Securities [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Trading account assets     35,000,000      
Total trading account liabilities     16,000,000      
Fair Value Inputs Level 2 [Member] | Recurring Fair Value Measurements [Member] | Federal Agency Securities [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Securities available for sale 235,000,000   147,000,000      
Fair Value Inputs Level 2 [Member] | Recurring Fair Value Measurements [Member] | Commercial Non-Agency [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Securities available for sale 637,000,000   321,000,000      
Fair Value Inputs Level 2 [Member] | Recurring Fair Value Measurements [Member] | Corporate And Other Debt Securities [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Securities available for sale 1,549,000,000   537,000,000      
Fair Value Inputs Level 2 [Member] | Recurring Fair Value Measurements [Member] | Interest Rate Swaps [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Total derivative assets 2,059,000,000   2,758,000,000      
Total derivative liabilities 1,953,000,000   2,416,000,000      
Fair Value Inputs Level 2 [Member] | Recurring Fair Value Measurements [Member] | Interest Rate Options [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Total derivative assets 4,000,000   28,000,000      
Total derivative liabilities 4,000,000   28,000,000      
Fair Value Inputs Level 2 [Member] | Recurring Fair Value Measurements [Member] | Interest Rate Futures And Forward Commitments [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Total derivative assets 8,000,000   11,000,000      
Total derivative liabilities 22,000,000   34,000,000      
Fair Value Inputs Level 2 [Member] | Recurring Fair Value Measurements [Member] | Other Contracts [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Total derivative assets 48,000,000   43,000,000      
Total derivative liabilities 46,000,000   36,000,000      
Fair Value Inputs Level 2 [Member] | Nonrecurring Fair Value Measurements [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Loans held for sale 31,000,000   36,000,000      
Foreclosed property, other real estate and equipment 70,000,000   91,000,000      
Fair Value Inputs Level 3 [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Securities available for sale 16,000,000          
Loans held for sale 206,000,000          
Fair Value Inputs Level 3 [Member] | Recurring Fair Value Measurements [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Trading account assets     191,000,000 [1]      
Securities available for sale 16,000,000   36,000,000      
Mortgage servicing rights 179,000,000   182,000,000      
Total derivative assets 30,000,000 [4],[5]   13,000,000 [4],[5]      
Total trading account liabilities     7,000,000 [2]      
Fair Value Inputs Level 3 [Member] | Recurring Fair Value Measurements [Member] | Obligations Of States And Political Subdivisions [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Trading account assets     139,000,000      
Securities available for sale     20,000,000      
Fair Value Inputs Level 3 [Member] | Recurring Fair Value Measurements [Member] | Commercial Agency [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Trading account assets     51,000,000      
Total trading account liabilities     5,000,000      
Fair Value Inputs Level 3 [Member] | Recurring Fair Value Measurements [Member] | Other Securities [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Trading account assets     1,000,000      
Total trading account liabilities     2,000,000      
Fair Value Inputs Level 3 [Member] | Recurring Fair Value Measurements [Member] | Residential Non-Agency [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Securities available for sale 14,000,000   16,000,000      
Fair Value Inputs Level 3 [Member] | Recurring Fair Value Measurements [Member] | Corporate And Other Debt Securities [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Securities available for sale 2,000,000          
Fair Value Inputs Level 3 [Member] | Recurring Fair Value Measurements [Member] | Interest Rate Options [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Total derivative assets 30,000,000   13,000,000      
Fair Value Inputs Level 3 [Member] | Nonrecurring Fair Value Measurements [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Loans held for sale 77,000,000   195,000,000      
Foreclosed property, other real estate and equipment 48,000,000   162,000,000      
Estimated Fair Value [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Total derivative liabilities 2,025,000,000 [4],[5]   2,514,000,000 [4],[5]      
Estimated Fair Value [Member] | Recurring Fair Value Measurements [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Trading account assets 110,000,000 [1]   1,266,000,000 [1]      
Securities available for sale 26,617,000,000   23,771,000,000      
Mortgage loans held for sale 950,000,000   844,000,000      
Mortgage servicing rights 179,000,000   182,000,000      
Total derivative assets 2,149,000,000 [4],[5]   2,853,000,000 [4],[5]      
Total trading account liabilities     256,000,000 [2]      
Estimated Fair Value [Member] | Recurring Fair Value Measurements [Member] | U.S. Treasury Securities [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Trading account assets     215,000,000      
Securities available for sale 51,000,000   98,000,000      
Total trading account liabilities     97,000,000      
Estimated Fair Value [Member] | Recurring Fair Value Measurements [Member] | Obligations Of States And Political Subdivisions [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Trading account assets     240,000,000      
Securities available for sale 14,000,000   36,000,000      
Total trading account liabilities     2,000,000      
Estimated Fair Value [Member] | Recurring Fair Value Measurements [Member] | Residential Agency [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Trading account assets     359,000,000      
Securities available for sale 23,494,000,000   22,175,000,000      
Total trading account liabilities     133,000,000      
Estimated Fair Value [Member] | Recurring Fair Value Measurements [Member] | Commercial Agency [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Trading account assets     51,000,000      
Securities available for sale 514,000,000   326,000,000      
Total trading account liabilities     5,000,000      
Estimated Fair Value [Member] | Recurring Fair Value Measurements [Member] | Other Securities [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Trading account assets     36,000,000      
Total trading account liabilities     18,000,000      
Estimated Fair Value [Member] | Recurring Fair Value Measurements [Member] | Equity Securities [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Trading account assets 110,000,000   365,000,000      
Securities available for sale 107,000,000 [3]   115,000,000 [3]      
Total trading account liabilities     1,000,000      
Estimated Fair Value [Member] | Recurring Fair Value Measurements [Member] | Federal Agency Securities [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Securities available for sale 235,000,000   147,000,000      
Estimated Fair Value [Member] | Recurring Fair Value Measurements [Member] | Residential Non-Agency [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Securities available for sale 14,000,000   16,000,000      
Estimated Fair Value [Member] | Recurring Fair Value Measurements [Member] | Commercial Non-Agency [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Securities available for sale 637,000,000   321,000,000      
Estimated Fair Value [Member] | Recurring Fair Value Measurements [Member] | Corporate And Other Debt Securities [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Securities available for sale 1,551,000,000   537,000,000      
Estimated Fair Value [Member] | Recurring Fair Value Measurements [Member] | Interest Rate Swaps [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Total derivative assets 2,059,000,000   2,758,000,000      
Total derivative liabilities 1,953,000,000   2,416,000,000      
Estimated Fair Value [Member] | Recurring Fair Value Measurements [Member] | Interest Rate Options [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Total derivative assets 34,000,000   41,000,000      
Total derivative liabilities 4,000,000   28,000,000      
Estimated Fair Value [Member] | Recurring Fair Value Measurements [Member] | Interest Rate Futures And Forward Commitments [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Total derivative assets 8,000,000   11,000,000      
Total derivative liabilities 22,000,000   34,000,000      
Estimated Fair Value [Member] | Recurring Fair Value Measurements [Member] | Other Contracts [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Total derivative assets 48,000,000   43,000,000      
Total derivative liabilities 46,000,000   36,000,000      
Estimated Fair Value [Member] | Nonrecurring Fair Value Measurements [Member]
            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Loans held for sale 108,000,000   231,000,000      
Foreclosed property, other real estate and equipment $ 118,000,000   $ 253,000,000      
[1] All trading account assets at December 31, 2011 were related to Morgan Keegan (see Note 2 for further discussion regarding the sale of Morgan Keegan) with the exception of $178 million of which all were classified as Level 1 in the table. The Morgan Keegan items do not appear in the June 30, 2012 amounts, as the sale was closed during the second quarter of 2012.
[2] All trading account liabilities are related to Morgan Keegan at December 31, 2011. These items do not appear in the June 30, 2012 amounts as they were included with the sale of Morgan Keegan.
[3] Excludes Federal Reserve Bank and Federal Home Loan Bank stock totaling $480 million and $135 million at June 30, 2012 and $481 million and $219 million December 31, 2011, respectively.
[4] At June 30, 2012, derivatives include approximately $1.2 billion related to legally enforceable master netting agreements that allow the Company to settle positive and negative positions. Derivatives are also presented excluding cash collateral received of $57 million and cash collateral posted of $881 million with counterparties. At December 31, 2011, derivatives include approximately $1.4 billion related to legally enforceable master netting agreements that allow the Company to settle positive and negative positions. Derivatives are also presented excluding cash collateral received of $55 million and cash collateral posted of $732 million with counterparties.
[5] Derivative assets and liabilities both include $454 million of interest rate swaps and $23 million of interest rate options at December 31, 2011 related to Morgan Keegan, all of which are classified as Level 2 in the table. These items do not appear in the June 30, 2012 amounts, as they were included with the sale of Morgan Keegan.