Aggregate dividends declared during the period for each share of common stock outstanding.

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Amount of paid and unpaid common stock dividends declared with the form of settlement in cash.

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Amount of paid and unpaid preferred stock dividends declared with the form of settlement in cash.

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The per share liquidation preference (or restrictions) of nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) that has a preference in involuntary liquidation considerably in excess of the par or stated value of the shares. The liquidation preference is the difference between the preference in liquidation and the par or stated values of the share.

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The redemption (or callable) amount of currently redeemable preferred stock. Includes amounts representing dividends not currently declared or paid but which will be payable under the redemption features or for which ultimate payment is solely within the control of the issuer.

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Shareholders' Equity - Schedule of Dividends Declared (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 15, 2020	Sep. 30, 2018	Apr. 30, 2016	May 31, 2015	Feb. 28, 2014
Dividends Payable [Line Items]
Preferred stock cash dividend	$ 44	$ 55
Cash dividends declared (in USD per share)	$ 0.52	$ 0.47
Common stock dividends	$ 183	$ 177
Series C Preferred Stock
Dividends Payable [Line Items]
Preferred dividends declared (USD per share)	$ 1,313	$ 1,313
Preferred stock cash dividend	$ 6	$ 6
Preferred stock, redemption amount			$ 500
Liquidation preference per share (USD per share)			$ 100,000
Series C Preferred Stock, Depository Share
Dividends Payable [Line Items]
Preferred dividends declared (USD per share)	$ 0.33	$ 0.33
Liquidation preference per share (USD per share)			$ 25.00
Series D Preferred Stock
Dividends Payable [Line Items]
Preferred dividends declared (USD per share)	$ 1,475	$ 1,475
Preferred stock cash dividend	$ 11	$ 11
Liquidation preference per share (USD per share)							$ 100,000
Series D Preferred Stock, Depository Share
Dividends Payable [Line Items]
Preferred dividends declared (USD per share)	$ 0.37	$ 0.37
Liquidation preference per share (USD per share)							$ 25
Series E Preferred Stock
Dividends Payable [Line Items]
Preferred dividends declared (USD per share)	$ 0	$ 1,500
Preferred stock cash dividend	$ 0	$ 11
Preferred stock, redemption amount			$ 750
Liquidation preference per share (USD per share)			$ 100,000
Series E Preferred Stock, Depository Share
Dividends Payable [Line Items]
Preferred dividends declared (USD per share)	$ 0	$ 0.38
Liquidation preference per share (USD per share)			$ 25.00
Series F Preferred Stock
Dividends Payable [Line Items]
Preferred dividends declared (USD per share)	$ 2,625	$ 2,625
Preferred stock cash dividend	$ 20	$ 20
Liquidation preference per share (USD per share)						$ 100,000
Series F Preferred Stock, Depository Share
Dividends Payable [Line Items]
Preferred dividends declared (USD per share)	$ 26.25	$ 26.25
Liquidation preference per share (USD per share)						$ 1,000
Series G Preferred Stock
Dividends Payable [Line Items]
Preferred dividends declared (USD per share)	$ 1,338	$ 1,338
Preferred stock cash dividend	$ 7	$ 7
Liquidation preference per share (USD per share)					$ 100,000
Series G Preferred Stock, Depository Share
Dividends Payable [Line Items]
Preferred dividends declared (USD per share)	$ 0.33	$ 0.33
Liquidation preference per share (USD per share)					$ 25
Series H Preferred Stock
Dividends Payable [Line Items]
Preferred dividends declared (USD per share)	$ 0	$ 0
Preferred stock cash dividend	$ 0	$ 0
Liquidation preference per share (USD per share)				$ 100,000
Series H Preferred Stock, Depository Share
Dividends Payable [Line Items]
Preferred dividends declared (USD per share)	$ 0	$ 0
Liquidation preference per share (USD per share)				$ 1,000