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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Minimum Capital Conservation Buffer

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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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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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Tier 1 Risk Based Capital as defined in the regulations.

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

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Regulatory Capital and Other Regulatory Matters (Schedule of Regulatory Capital Amount and Ratios) (Details) - USD ($) $ / shares in Units, $ in Millions	Apr. 10, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Aug. 22, 2017	Jun. 30, 2017	Jun. 28, 2017	Apr. 14, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 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%
Tier One Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets		6.00%
Capital Required for Capital Adequacy to Risk Weighted Assets		8.00%
Common equity Tier 1 capital conservation buffer		2.50%
BHC Stress Test Threshold		$ 50,000
Federal Reserve Bank Stock		$ 446	$ 445
Minimum Capital Conservation Buffer		1.875%	1.25%
Increase in Minimum Capital Conservation Buffer		2.50%
Increase (Decrease) in Dividends Payable		50.00%
FRB Approved Capital Action - Dividends							$ 0.12					$ 0.08
Increase (decrease) in share repurchase program		9.00%
Stock Repurchase Program, Authorized Amount		$ 760
Dividends Payable, Amount Per Share		$ 0.13	$ 0.12	$ 0.12		$ 0.08		$ 0.08	$ 0.08	$ 0.08	$ 0.08
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%
Tier One Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets		6.00%
Capital Required for Capital Adequacy to Risk Weighted Assets		8.00%
Tier One Leverage Capital Required for Capital Adequacy to Average Assets		4.00%
Common Equity Tier 1 Capital		$ 13,079	$ 13,237
Percentage of Common Equity Tier 1 Capital to Risk-weighted Assets		9.26%	9.53%
Tier One Risk Based Capital		$ 15,512	$ 15,628
Tier One Risk Based Capital to Risk Weighted Assets		10.98%	11.25%
Tier One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets		6.00%
Capital		$ 17,760	$ 17,974
Capital to Risk Weighted Assets		12.57%	12.94%
Capital Required to be Well Capitalized to Risk Weighted Assets		10.00%
Tier One Leverage Capital		$ 15,512	$ 15,628
Tier One Leverage Capital to Average Assets		9.26%	9.53%
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%
Tier One Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets		6.00%
Capital Required for Capital Adequacy to Risk Weighted Assets		8.00%
Tier One Leverage Capital Required for Capital Adequacy to Average Assets		4.00%			15.00%
Common Equity Tier 1 Capital		$ 16,535	$ 17,059
Percentage of Common Equity Tier 1 Capital to Risk-weighted Assets		13.93%	15.04%
Common Equity Tier 1 Capital Required to be Well Capitalized to Risk-weighted Assets		6.50%
Tier One Risk Based Capital		$ 16,535	$ 17,059
Tier One Risk Based Capital to Risk Weighted Assets		13.93%	15.04%
Tier One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets		8.00%
Capital		$ 17,480	$ 17,886
Capital to Risk Weighted Assets		14.72%	15.77%
Capital Required to be Well Capitalized to Risk Weighted Assets		10.00%
Tier One Leverage Capital		$ 16,535	$ 17,059
Tier One Leverage Capital to Average Assets		11.94%	12.87%
Tier One Leverage Capital Required to be Well Capitalized to Average Assets		5.00%
Subsequent Event [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Dividends Payable, Amount Per Share	$ 0.13