v2.4.0.6
Regulatory Capital and Ratios (Detail) (USD $)
In Millions, unless otherwise specified
Mar. 31, 2013
Tier 1 Risk-Based Capital  
Actual Amount $ 5,836
Minimum Capital Requirement Amount 1,259
Minimum to be Well Capitalized Amount 1,889
Actual Ratio 18.50%
Minimum Capital Requirement Ratio 4.00%
Minimum to be Well Capitalized Ratio 6.00%
Total Risk-Based Capital  
Actual Amount 5,896
Minimum Capital Requirement Amount 2,518
Minimum to be Well Capitalized Amount 3,148
Actual Ratio 18.70%
Minimum Capital Requirement Ratio 8.00%
Minimum to be Well Capitalized Ratio 10.00%
Tier 1 Leverage  
Actual Amount 5,836
Minimum Capital Requirement Amount 3,538
Minimum to be Well Capitalized Amount 4,423
Actual Ratio 6.60%
Minimum Capital Requirement Ratio 4.00%
Minimum to be Well Capitalized Ratio 5.00%
Tangible Equity  
Actual Amount 5,836
Minimum Capital Requirement Amount $ 1,769
Actual Ratio 6.60%
Minimum Capital Requirement Ratio 2.00%