CONSOLIDATED BALANCE SHEET (Parenthetical) (USD $) In Millions, except Share data, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Federal funds sold and securities borrowed or purchased under agreements to resell, at fair value	$ 239,015	$ 242,570
Trading account assets, pledged to creditors	105,710us-gaap_TradingSecuritiesRestricted	106,217us-gaap_TradingSecuritiesRestricted
Available-for-sale securities, pledged to creditors	12,595	13,808
Held-to-maturity securities, pledged to creditors	2,849	2,974
Non-marketable equity securities, pledged to creditors	2,570	2,758
Loans, net of unearned income	621,054	644,635
Other assets	136,040us-gaap_OtherAssets	122,122us-gaap_OtherAssets
Interest-bearing deposits in U.S. offices	275,423	284,978
Interest-bearing deposits in offices outside the U.S.	416,003	414,471
Federal funds purchased and securities loaned or sold under agreements to repurchase (including $34,225 and $36,725 as of March 31, 2015 and December 31, 2014, respectively, at fair value)	175,371	173,438
Short-term borrowings	39,405us-gaap_ShortTermBorrowings	58,335us-gaap_ShortTermBorrowings
Long-term debt	210,522us-gaap_LongTermDebt	223,080us-gaap_LongTermDebt
Other liabilities	90,143us-gaap_OtherLiabilities	85,084us-gaap_OtherLiabilities
Preferred stock, par value (in dollars per share)	$ 1.00	$ 1.00
Preferred stock, authorized shares (in shares)	30,000,000us-gaap_PreferredStockSharesAuthorized	30,000,000us-gaap_PreferredStockSharesAuthorized
Preferred stock, issued shares, at aggregate liquidation value (in shares)	478,720us-gaap_PreferredStockSharesIssued	418,720us-gaap_PreferredStockSharesIssued
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, authorized shares (in shares)	6,000,000,000us-gaap_CommonStockSharesAuthorized	6,000,000,000us-gaap_CommonStockSharesAuthorized
Common stock, issued shares (in shares)	3,099,470,853us-gaap_CommonStockSharesIssued	3,082,037,568us-gaap_CommonStockSharesIssued
Treasury stock (in shares)	65,331,175us-gaap_TreasuryStockShares	58,119,993us-gaap_TreasuryStockShares
Consumer
Loans, net of unearned income	341,706	369,970
Corporate
Loans, net of unearned income	279,348	274,665
Fair value
Federal funds sold and securities borrowed or purchased under agreements to resell, at fair value	135,894	144,191
Other assets	8,936	7,762
Interest-bearing deposits in U.S. offices	976	994
Interest-bearing deposits in offices outside the U.S.	674	690
Federal funds purchased and securities loaned or sold under agreements to repurchase (including $34,225 and $36,725 as of March 31, 2015 and December 31, 2014, respectively, at fair value)	34,225	36,725
Short-term borrowings	926	1,496
Long-term debt	25,409	26,180
Other liabilities	2,024	1,776
Fair value \| Consumer
Loans, net of unearned income	38	43
Fair value \| Corporate
Loans, net of unearned income	6,537	5,858
Consolidated VIEs
Loans, net of unearned income	87,932	95,979
Other assets	4,758	619
Short-term borrowings	14,840	20,254
Long-term debt	35,251	40,078
Other liabilities	3,983	901
Consolidated VIEs \| Consumer
Loans, net of unearned income	58,790	66,383
Consolidated VIEs \| Corporate
Loans, net of unearned income	29,142	29,596
Consolidated VIEs \| Fair value
Long-term debt	0	0
Consolidated VIEs \| Fair value \| Consumer
Loans, net of unearned income	0	0
Consolidated VIEs \| Fair value \| Corporate
Loans, net of unearned income	$ 0	$ 0

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