Consolidated Statement of Condition (Parenthetical) (USD $) In Millions, except Share data, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Current Assets:
Investment securities held to maturity, fair value	$ 16,417	$ 17,842
Loans and leases, allowance for losses	41	38
Premises and equipment, accumulated depreciation	$ 4,653	$ 4,599
Stockholders' Equity:
Common stock, par value (in dollars per share)	$ 1	$ 1
Common stock, shares authorized (in shares)	750,000,000us-gaap_CommonStockSharesAuthorized	750,000,000us-gaap_CommonStockSharesAuthorized
Common stock, shares issued (in shares)	503,879,642us-gaap_CommonStockSharesIssued	503,880,120us-gaap_CommonStockSharesIssued
Preferred stock, shares authorized (in shares)	3,500,000us-gaap_PreferredStockSharesAuthorized	3,500,000us-gaap_PreferredStockSharesAuthorized
Treasury stock, shares (in shares)	92,569,079us-gaap_TreasuryStockShares	88,684,969us-gaap_TreasuryStockShares
Series E Preferred Stock
Stockholders' Equity:
Preferred stock, shares issued (in shares)	7,500	0
Preferred stock, shares outstanding (in shares)	7,500	0
Series C Preferred Stock
Stockholders' Equity:
Preferred stock, shares issued (in shares)	5,000	5,000
Preferred stock, shares outstanding (in shares)	5,000	5,000
Series D Preferred Stock
Stockholders' Equity:
Preferred stock, shares issued (in shares)	7,500	0
Preferred stock, shares outstanding (in shares)	7,500	0

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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