Consolidated Statement of Condition (Parenthetical) (USD $) In Millions, except Share data, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Current Assets:
Investment securities held to maturity, fair value	$ 16,543	$ 11,661
Loans and leases, allowance for losses	22	22
Premises and equipment, accumulated depreciation	$ 4,319	$ 4,037
Stockholders' Equity:
Common stock, par value (in dollars per share)	$ 1	$ 1
Common stock, shares authorized (in shares)	750,000,000	750,000,000
Common stock, shares issued (in shares)	503,885,462	503,900,268
Preferred stock, shares authorized (in shares)	3,500,000	3,500,000
Treasury stock, shares (in shares)	62,587,206	45,238,208
Series C Preferred Stock
Stockholders' Equity:
Preferred stock, shares issued, Series C (in shares)	5,000	5,000
Preferred stock, shares outstanding, Series C (in shares)	5,000	5,000