Regulatory Requirements (Capital Measures) (Details) (USD $) In Millions, unless otherwise specified	Jun. 30, 2011	Dec. 31, 2010
Balance
Tier 1 capital	$ 51,007	$ 52,880
Total capital	55,758	54,477
RWAs	304,759	329,560
Adjusted average assets	848,329	802,283
Tier 1 leverage
Ratio
Tier 1 capital, ratio	16.70%	16.10%
Total capital	18.30%	16.50%
RWAs
Adjusted average assets
Tier 1 leverage	6.00%	6.60%

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The amount of total capital as defined in the regulations.

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Total Capital divided by risk weighted assets as defined in the regulations.

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The amount of excess Total Capital divided by risk weighted assets which are assets that are weighted for credit risk according to a formula used by the Reserve Bank.

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Tier 1 Leverage Capital as defined in the regulations. Also called Core Capital.

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Tier 1 Leverage Capital divided by average assets as defined in the regulations.

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Tier 1 Risk Based Capital as defined in the regulations.

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The minimum amount of Tier 1 Risk Based Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The minimum Tier One Capital Ratio (Tier one capital divided by risk-weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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Tier 1 capital divided by risk weighted assets as defined by regulations.

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