Total Equity - Preferred Stock Outstanding (Details) - USD ($) $ / shares in Units, $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Class of Stock
Preferred stock carrying value	$ 8,520	$ 8,520
Preferred stock shares authorized (shares)	30,000,000
Series A
Class of Stock
Preferred stock shares outstanding (shares)	44,000
Liquidation preference per share (USD per share)	$ 25,000
Preferred stock carrying value	$ 1,100	1,100
Series C
Class of Stock
Preferred stock shares outstanding (shares)	519,882
Liquidation preference per share (USD per share)	$ 1,000
Preferred stock carrying value	$ 408	408
Series C \| MUFG
Class of Stock
Preferred stock shares issued (shares)	1,160,791
Preferred stock aggregate purchase price	$ 911
Preferred stock redemption (shares)	640,909
Preferred stock redemption amount	$ 503
Preferred stock converted to common shares	$ 705
Series E
Class of Stock
Preferred stock shares outstanding (shares)	34,500
Liquidation preference per share (USD per share)	$ 25,000
Preferred stock carrying value	$ 862	862
Series F
Class of Stock
Preferred stock shares outstanding (shares)	34,000
Liquidation preference per share (USD per share)	$ 25,000
Preferred stock carrying value	$ 850	850
Series G
Class of Stock
Preferred stock shares outstanding (shares)	20,000
Liquidation preference per share (USD per share)	$ 25,000
Preferred stock carrying value	$ 500	500
Series H
Class of Stock
Preferred stock shares outstanding (shares)	52,000
Liquidation preference per share (USD per share)	$ 25,000
Preferred stock carrying value	$ 1,300	1,300
Series I
Class of Stock
Preferred stock shares outstanding (shares)	40,000
Liquidation preference per share (USD per share)	$ 25,000
Preferred stock carrying value	$ 1,000	1,000
Series J
Class of Stock
Preferred stock shares outstanding (shares)	60,000
Liquidation preference per share (USD per share)	$ 25,000
Preferred stock carrying value	$ 1,500	1,500
Series K
Class of Stock
Preferred stock shares outstanding (shares)	40,000
Liquidation preference per share (USD per share)	$ 25,000
Preferred stock carrying value	$ 1,000	$ 1,000

Value of convertible preferred stock that was converted to common stock as of a particular date.

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Call price of preferred stock plus any dividends in arrears times total number of preferred stock outstanding.

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Number of preferred stock redeemed.

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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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The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

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Total number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) issued to shareholders (includes related preferred shares that were issued, repurchased, and remain in the treasury). May be all or portion of the number of preferred shares authorized. Excludes preferred shares that are classified as debt.

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Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

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