Regulatory Requirements (Capital Measures) (Details) - USD ($) $ in Millions	Jun. 30, 2017	Dec. 31, 2016
Advanced Approach
Balance
Common Equity Tier 1 capital	$ 61,604	$ 60,398
Tier 1 capital	70,380	68,097
Total capital	81,025	78,642
Assets
Total RWAs	$ 370,679	$ 358,141
Ratio
Common Equity Tier 1 capital	16.60%	16.90%
Tier 1 capital	19.00%	19.00%
Total capital	21.90%	22.00%
Minimum Capital Ratio
Common Equity Tier 1 capital	7.30%	5.90%
Tier 1 capital	8.80%	7.40%
Total capital	10.80%	9.40%
Standardized Approach
Assets
Adjusted average assets	$ 828,365	$ 811,402
Ratio
Tier 1 leverage	8.50%	8.40%
Minimum Capital Ratio
Tier 1 leverage	4.00%	4.00%

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Tier 1 Risk Based Common Capital as defined in the regulations.

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The minimum common equity Tier One Capital Ratio (Common equity 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 common capital divided by risk weighted assets as defined by regulations.

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The amount of total capital as defined in the regulations.

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The minimum Total risk based capital ratio (total capital divided by risk weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The minimum amount of Tier 1 Leverage Capital for capital adequacy purposes divided by average assets as defined in the regulations.

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