Consolidated Balance Sheet (Unaudited) (Parenthetical) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Held-to-maturity securities, Fair Value	$ 45,735	$ 44,964
Securities, pledged as collateral	1,000	2,100
Mortgage loans, carried at fair value	$ 2,690	$ 2,035
Common stock, par value	$ 0.01	$ 0.01
Common stock, share-authorized (actual number of shares)	4,000,000,000	4,000,000,000
Common stock, shares issued (actual number of shares)	2,125,725,742	2,125,725,742
Treasury stock, shares (actual number of shares)	526,688,641	517,391,021
Time deposits greater than 250,000	$ 15,600	$ 15,300
Available-for-Sale Securities [Member]
Securities, pledged as collateral	1,012	2,057
Trading Assets, Excluding Debt and Equity Securities [Member]
Securities, pledged as collateral	$ 988	$ 843

Face amount or stated value per share of common stock.

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Fair value of financial instrument held by the entity for its own account (proprietary securities) for trading or investment purposes that are carried at fair value and pledged to counterparties as collateral for financing transactions where counterparty has the right to re-pledge such.

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

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Fair value portion of mortgage loans held-for-sale.

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Amount of time deposit liabilities, including certificates of deposit, in denominations that meet or exceed the Federal Deposit Insurance Corporation (FDIC) insurance limit.

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Number of previously issued common shares repurchased by the issuing entity and held in treasury.

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