Consolidated Balance Sheet (Parenthetical) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Held-to-maturity securities, Fair Value	$ 44,964	$ 43,723
Securities, pledged as collateral	2,100	689
Mortgage loans, carried at fair value	$ 2,035	$ 3,534
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)	517,391,021	470,080,231
Time deposits greater than 250,000	$ 15,300	$ 6,800
Available-for-Sale Securities [Member]
Securities, pledged as collateral	2,057	689
Trading Assets, Excluding Debt and Equity Securities [Member]
Securities, pledged as collateral	$ 843	$ 238

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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