INTEREST REVENUE AND EXPENSE (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Interest revenue
Loan interest, including fees	$ 11,300	$ 11,774	$ 22,725	$ 24,015
Deposits with banks	252	329	508	694
Federal funds sold and securities borrowed or purchased under agreements to resell	702	902	1,390	1,845
Investments, including dividends	1,687	1,854	3,489	3,764
Trading account assets	1,669	1,695	3,299	3,392
Other interest	230	132	389	270
Total interest revenue	15,840	16,686	31,800	33,980
Interest expense
Deposits	1,583	1,933	3,259	3,943
Federal funds purchased and securities loaned or sold under agreements to repurchase	630	753	1,239	1,448
Trading account liabilities	43	52	85	105
Short-term borrowings	148	183	311	391
Long-term debt	1,754	2,422	3,594	5,034
Total interest expense	4,158	5,343	8,488	10,921
Net interest revenue	11,682	11,343	23,312	23,059
Provision for loan losses	1,827	2,475	4,041	5,184
Net interest revenue after provision for loan losses	9,855	8,868	19,271	17,875
Insurance fees and charges	$ 289	$ 297	$ 588	$ 669