Consolidated Balance Sheet (Unaudited) (Parenthetical) - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Held-to-maturity securities, Fair Value	$ 43,408	$ 43,723
Securities, pledged as collateral	571	689
Mortgage loans, carried at fair value	$ 3,271	$ 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)	476,747,913	470,080,231
Time deposits greater than 250,000	$ 7,800	$ 6,800
Available-for-Sale Securities [Member]
Securities, pledged as collateral	571	689
Trading Securities [Member]
Securities, pledged as collateral	$ 829	$ 238

Face amount or stated value per share of common stock.

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Fair value of investments in debt securities classified as held-to-maturity.

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