Bank holding companies with assets greater than $50 billion must develop and maintain a capital plan annually.

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Common Equity Tier 1 Capital Required to be Well Capitalized to Risk-weighted Assets

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Common equity Tier 1 capital conservation buffer

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FRB Approved Capital Action - Dividends

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Increase (decrease) in shares of common stock outstanding

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Percentage of Common Equity Tier 1 Capital to Risk-weighted Assets

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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 Total risk based capital ratio (total capital divided by risk weighted assets) required to be categorized as "well capitalized", in the regulatory framework for prompt corrective action.

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

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The per share amount of a dividend declared, but not paid, as of the financial reporting date.

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Federal Reserve Bank stock represents an equity interest in the Federal Reserve Bank. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

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Amount of stock repurchase plan authorized.

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

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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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The amount of Tier 1 Leverage Capital required to be categorized as well capitalized divided by average assets as defined in the regulatory framework for prompt corrective action.

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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 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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The Tier 1 capital ratio (Tier 1 capital divided by risk weighted assets) required to be categorized as "well capitalized" 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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Number of previously issued common shares repurchased by the issuing entity and held in treasury.

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Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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Regulatory Capital and Other Regulatory Matters (Schedule of Regulatory Capital Amount and Ratios) (Details) - USD ($) $ / shares in Units, $ in Millions	6 Months Ended		12 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jul. 18, 2017	Jun. 28, 2017	Jan. 11, 2017	Dec. 31, 2016	Oct. 18, 2016	Sep. 30, 2016	Jul. 18, 2016	Jun. 29, 2016
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Common Equity Tier 1 Capital Required for Capital Adequacy to Risk-weighted Assets	4.50%		4.50%
Tier One Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets	6.00%		6.00%
Capital Required for Capital Adequacy to Risk Weighted Assets	8.00%		8.00%
Common equity Tier 1 capital conservation buffer	2.50%		2.50%
Federal Reserve Bank Stock	$ 444		$ 444				$ 435
assets greater than $50 billion	50,000		50,000
FRB Approved Capital Action - Dividends					$ 0.12						$ 0.08
Stock Repurchase Program, Authorized Amount	$ 700		$ 700
Dividends Payable, Amount Per Share	$ 0.08		$ 0.08			$ 0.08		$ 0.08	$ 0.08	$ 0.08
Treasury Stock, Value, Acquired, Cost Method	$ 373	$ 14	$ 699
Treasury Stock, Common, Shares	35,625,615		35,625,615
Common Stock, Shares, Outstanding	452,291,918	483,753,360	452,291,918				467,000,306
Increase (decrease) in shares of common stock outstanding		6.50%
Increase (Decrease) in Dividends Payable	50.00%		50.00%
Increase (decrease) in share repurchase program	9.00%		9.00%
Subsequent Event [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Dividends Payable, Amount Per Share				$ 0.12
Parent Company [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Common Equity Tier 1 Capital Required for Capital Adequacy to Risk-weighted Assets	4.50%		4.50%
Tier One Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets	6.00%		6.00%
Capital Required for Capital Adequacy to Risk Weighted Assets	8.00%		8.00%
Tier One Leverage Capital Required for Capital Adequacy to Average Assets	4.00%		4.00%
Common Equity Tier 1 Capital	$ 13,066		$ 13,066				$ 12,978
Percentage of Common Equity Tier 1 Capital to Risk-weighted Assets	9.47%		9.47%				9.37%
Tier One Risk Based Capital	$ 15,417		$ 15,417				$ 15,147
Tier One Risk Based Capital to Risk Weighted Assets	11.18%		11.18%				10.93%
Tier One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets	6.00%		6.00%
Capital	$ 17,704		$ 17,704				$ 17,419
Capital to Risk Weighted Assets	12.83%		12.83%				12.57%
Capital Required to be Well Capitalized to Risk Weighted Assets	10.00%		10.00%
Tier One Leverage Capital	$ 15,417		$ 15,417				$ 15,147
Tier One Leverage Capital to Average Assets	9.51%		9.51%				9.54%
Subsidiaries [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Common Equity Tier 1 Capital Required for Capital Adequacy to Risk-weighted Assets	4.50%		4.50%
Tier One Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets	6.00%		6.00%
Capital Required for Capital Adequacy to Risk Weighted Assets	8.00%		8.00%
Tier One Leverage Capital Required for Capital Adequacy to Average Assets	15.00%		15.00%
Common Equity Tier 1 Capital	$ 18,975		$ 18,975				$ 17,888
Percentage of Common Equity Tier 1 Capital to Risk-weighted Assets	17.89%		17.89%				16.70%
Common Equity Tier 1 Capital Required to be Well Capitalized to Risk-weighted Assets	6.50%		6.50%
Tier One Risk Based Capital	$ 18,975		$ 18,975				$ 17,888
Tier One Risk Based Capital to Risk Weighted Assets	17.89%		17.89%				16.70%
Tier One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets	8.00%		8.00%
Capital	$ 19,651		$ 19,651				$ 18,458
Capital to Risk Weighted Assets	18.53%		18.53%				17.24%
Capital Required to be Well Capitalized to Risk Weighted Assets	10.00%		10.00%
Tier One Leverage Capital	$ 18,975		$ 18,975				$ 17,888
Tier One Leverage Capital to Average Assets	15.31%		15.31%				15.21%
Tier One Leverage Capital Required to be Well Capitalized to Average Assets	5.00%		5.00%
2017 through 2018 [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Stock Repurchase Program, Authorized Amount	$ 760		$ 760