Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Statement of Financial Position [Abstract]
HTM securities, Fair Value	$ 20,047	$ 22,837
Preferred stock, par value (in dollars per share)	$ 5	$ 5
Preferred stock, liquidation preference (in dollars per share)	25,000	25,000
Common stock, par value (in dollars per share)	$ 5	$ 5

Face amount or stated value per share of common stock.

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Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

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The price per share at which the preferred stock of an entity that has priority over common stock in the distribution of dividends and in the event of liquidation of the entity is redeemed or may be called at. The redemption features of this preferred stock are solely within the control of the issuer.

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