DERIVATIVES ACTIVITIES (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Trading derivatives
Derivatives
Derivative notionals	$ 52,917,009	$ 49,258,619
Trading derivatives | Interest rate contracts
Derivatives
Derivative notionals	42,520,342	39,379,717
Trading derivatives | Interest rate contracts | Swaps
Derivatives
Derivative notionals	29,882,342	28,069,960
Trading derivatives | Interest rate contracts | Futures and forwards
Derivatives
Derivative notionals	5,125,812	3,549,642
Trading derivatives | Interest rate contracts | Written options
Derivatives
Derivative notionals	3,872,194	3,871,700
Trading derivatives | Interest rate contracts | Purchased options
Derivatives
Derivative notionals	3,639,994	3,888,415
Trading derivatives | Foreign exchange contracts
Derivatives
Derivative notionals	6,317,175	5,549,759
Trading derivatives | Foreign exchange contracts | Swaps
Derivatives
Derivative notionals	1,392,390	1,182,363
Trading derivatives | Foreign exchange contracts | Futures and forwards
Derivatives
Derivative notionals	3,402,183	3,191,687
Trading derivatives | Foreign exchange contracts | Written options
Derivatives
Derivative notionals	761,308	591,818
Trading derivatives | Foreign exchange contracts | Purchased options
Derivatives
Derivative notionals	761,294	583,891
Trading derivatives | Equity contracts
Derivatives
Derivative notionals	803,764	1,161,515
Trading derivatives | Equity contracts | Swaps
Derivatives
Derivative notionals	95,632	86,978
Trading derivatives | Equity contracts | Futures and forwards
Derivatives
Derivative notionals	16,799	12,882
Trading derivatives | Equity contracts | Written options
Derivatives
Derivative notionals	366,044	552,333
Trading derivatives | Equity contracts | Purchased options
Derivatives
Derivative notionals	325,289	509,322
Trading derivatives | Commodity and other contracts
Derivatives
Derivative notionals	325,139	286,377
Trading derivatives | Commodity and other contracts | Swaps
Derivatives
Derivative notionals	28,188	23,403
Trading derivatives | Commodity and other contracts | Futures and forwards
Derivatives
Derivative notionals	85,092	73,090
Trading derivatives | Commodity and other contracts | Written options
Derivatives
Derivative notionals	104,423	90,650
Trading derivatives | Commodity and other contracts | Purchased options
Derivatives
Derivative notionals	107,436	99,234
Trading derivatives | Credit derivatives
Derivatives
Derivative notionals	2,950,589	2,881,251
Trading derivatives | Credit derivatives | Protection sold
Derivatives
Derivative notionals	1,438,553	1,394,528
Trading derivatives | Credit derivatives | Protection purchased
Derivatives
Derivative notionals	1,512,036	1,486,723
Hedging instruments under ASC 815 (SFAS 133)
Derivatives
Derivative notionals	231,596	293,573
Hedging instruments under ASC 815 (SFAS 133) | Interest rate contracts
Derivatives
Derivative notionals	135,176	163,079
Hedging instruments under ASC 815 (SFAS 133) | Interest rate contracts | Swaps
Derivatives
Derivative notionals	135,176	163,079
Hedging instruments under ASC 815 (SFAS 133) | Foreign exchange contracts
Derivatives
Derivative notionals	94,252	126,241
Hedging instruments under ASC 815 (SFAS 133) | Foreign exchange contracts | Swaps
Derivatives
Derivative notionals	22,791	27,575
Hedging instruments under ASC 815 (SFAS 133) | Foreign exchange contracts | Futures and forwards
Derivatives
Derivative notionals	65,588	55,211
Hedging instruments under ASC 815 (SFAS 133) | Foreign exchange contracts | Written options
Derivatives
Derivative notionals	130	4,292
Hedging instruments under ASC 815 (SFAS 133) | Foreign exchange contracts | Purchased options
Derivatives
Derivative notionals	5,743	39,163
Hedging instruments under ASC 815 (SFAS 133) | Credit derivatives
Derivatives
Derivative notionals	2,168	4,253
Hedging instruments under ASC 815 (SFAS 133) | Credit derivatives | Protection purchased
Derivatives
Derivative notionals	2,168	4,253
Hedging instruments under ASC 815 (SFAS 133) | Net investment hedge
Derivatives
Derivative notionals	5,739	7,060
Management hedges
Derivatives
Derivative notionals	290,007	263,143
Management hedges | Interest rate contracts
Derivatives
Derivative notionals	208,472	187,433
Management hedges | Interest rate contracts | Swaps
Derivatives
Derivative notionals	125,308	119,344
Management hedges | Interest rate contracts | Futures and forwards
Derivatives
Derivative notionals	50,317	43,965
Management hedges | Interest rate contracts | Written options
Derivatives
Derivative notionals	25,067	16,786
Management hedges | Interest rate contracts | Purchased options
Derivatives
Derivative notionals	7,780	7,338
Management hedges | Foreign exchange contracts
Derivatives
Derivative notionals	56,248	53,796
Management hedges | Foreign exchange contracts | Swaps
Derivatives
Derivative notionals	16,452	22,458
Management hedges | Foreign exchange contracts | Futures and forwards
Derivatives
Derivative notionals	37,603	31,095
Management hedges | Foreign exchange contracts | Written options
Derivatives
Derivative notionals	137	190
Management hedges | Foreign exchange contracts | Purchased options
Derivatives
Derivative notionals	2,056	53
Management hedges | Credit derivatives
Derivatives
Derivative notionals	25,287	21,914
Management hedges | Credit derivatives | Protection purchased
Derivatives
Derivative notionals	$ 25,287	$ 21,914