Consolidated Balance Sheet (Parenthetical) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Securities, pledged as collateral	$ 850	$ 402
Mortgage loans, carried at fair value	$ 6,176	$ 8,524
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)	643,035,053	618,618,084
Time deposits greater than 250,000	$ 2,400	$ 4,400
Available-for-Sale Securities [Member]
Securities, pledged as collateral	850	402
Trading Assets, Excluding Debt and Equity Securities [Member]
Securities, pledged as collateral	$ 1,426	$ 1,255

Face amount or stated value per share of common stock.

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