Consolidated Balance Sheet (Parenthetical) (USD $) In Millions, except Share data	Sep. 30, 2011	Dec. 31, 2010
Investment securities
Held-to-maturity, fair value	$ 16,613	$ 1,419
Mortgage loans, carried at fair value	$ 5,152	$ 8,100
Shareholders' equity
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares 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)	213,050,586	204,822,330

Face amount or stated value of common stock per share; generally not indicative of the fair market value per share.

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