DERIVATIVES ACTIVITIES - Derivative Notionals (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Net investment hedge under ASC 815 (SFAS 133)
Derivatives
Derivative notionals	$ 3,664	$ 3,752
Hedging instruments under ASC 815 (SFAS 133)
Derivatives
Derivative notionals	274,786	262,813
Hedging instruments under ASC 815 (SFAS 133) | Interest rate contracts
Derivatives
Derivative notionals	182,718	163,348
Hedging instruments under ASC 815 (SFAS 133) | Interest rate contracts | Swaps
Derivatives
Derivative notionals	182,718	163,348
Hedging instruments under ASC 815 (SFAS 133) | Interest rate contracts | Futures and forwards
Derivatives
Derivative notionals	0	0
Hedging instruments under ASC 815 (SFAS 133) | Interest rate contract options | Written or Sold
Derivatives
Derivative notionals	0	0
Hedging instruments under ASC 815 (SFAS 133) | Interest rate contract options | Purchased
Derivatives
Derivative notionals	0	0
Hedging instruments under ASC 815 (SFAS 133) | Foreign exchange contracts
Derivatives
Derivative notionals	91,229	98,376
Hedging instruments under ASC 815 (SFAS 133) | Foreign exchange contracts | Swaps
Derivatives
Derivative notionals	25,322	25,157
Hedging instruments under ASC 815 (SFAS 133) | Foreign exchange contracts | Futures and forwards
Derivatives
Derivative notionals	65,907	73,219
Hedging instruments under ASC 815 (SFAS 133) | Foreign exchange contract options | Written or Sold
Derivatives
Derivative notionals	0	0
Hedging instruments under ASC 815 (SFAS 133) | Foreign exchange contract options | Purchased
Derivatives
Derivative notionals	0	0
Hedging instruments under ASC 815 (SFAS 133) | Equity contracts
Derivatives
Derivative notionals	0	0
Hedging instruments under ASC 815 (SFAS 133) | Equity contracts | Swaps
Derivatives
Derivative notionals	0	0
Hedging instruments under ASC 815 (SFAS 133) | Equity contracts | Futures and forwards
Derivatives
Derivative notionals	0	0
Hedging instruments under ASC 815 (SFAS 133) | Equity contract options | Written or Sold
Derivatives
Derivative notionals	0	0
Hedging instruments under ASC 815 (SFAS 133) | Equity contract options | Purchased
Derivatives
Derivative notionals	0	0
Hedging instruments under ASC 815 (SFAS 133) | Commodity and other contracts
Derivatives
Derivative notionals	839	1,089
Hedging instruments under ASC 815 (SFAS 133) | Commodity and other contracts | Swaps
Derivatives
Derivative notionals	0	0
Hedging instruments under ASC 815 (SFAS 133) | Commodity and other contracts | Futures and forwards
Derivatives
Derivative notionals	839	1,089
Hedging instruments under ASC 815 (SFAS 133) | Commodity and other contract options | Written or Sold
Derivatives
Derivative notionals	0	0
Hedging instruments under ASC 815 (SFAS 133) | Commodity and other contract options | Purchased
Derivatives
Derivative notionals	0	0
Hedging instruments under ASC 815 (SFAS 133) | Credit derivatives
Derivatives
Derivative notionals	0	0
Hedging instruments under ASC 815 (SFAS 133) | Credit derivatives | Written or Sold
Derivatives
Derivative notionals	0	0
Hedging instruments under ASC 815 (SFAS 133) | Credit derivatives | Purchased
Derivatives
Derivative notionals	0	0
Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Other derivative instruments, Trading derivatives
Derivatives
Derivative notionals	54,925,383	58,167,908
Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Other derivative instruments, Trading derivatives | Interest rate contracts
Derivatives
Derivative notionals	42,371,316	45,434,346
Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Other derivative instruments, Trading derivatives | Interest rate contracts | Swaps
Derivatives
Derivative notionals	27,746,788	31,906,549
Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Other derivative instruments, Trading derivatives | Interest rate contracts | Futures and forwards
Derivatives
Derivative notionals	8,526,874	7,044,990
Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Other derivative instruments, Trading derivatives | Interest rate contract options | Written or Sold
Derivatives
Derivative notionals	3,119,012	3,311,751
Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Other derivative instruments, Trading derivatives | Interest rate contract options | Purchased
Derivatives
Derivative notionals	2,978,642	3,171,056
Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Other derivative instruments, Trading derivatives | Foreign exchange contracts
Derivatives
Derivative notionals	9,292,529	9,429,652
Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Other derivative instruments, Trading derivatives | Foreign exchange contracts | Swaps
Derivatives
Derivative notionals	4,289,988	4,567,977
Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Other derivative instruments, Trading derivatives | Foreign exchange contracts | Futures and forwards
Derivatives
Derivative notionals	2,079,320	2,154,773
Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Other derivative instruments, Trading derivatives | Foreign exchange contract options | Written or Sold
Derivatives
Derivative notionals	1,457,861	1,343,520
Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Other derivative instruments, Trading derivatives | Foreign exchange contract options | Purchased
Derivatives
Derivative notionals	1,465,360	1,363,382
Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Other derivative instruments, Trading derivatives | Equity contracts
Derivatives
Derivative notionals	809,313	742,697
Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Other derivative instruments, Trading derivatives | Equity contracts | Swaps
Derivatives
Derivative notionals	137,748	131,344
Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Other derivative instruments, Trading derivatives | Equity contracts | Futures and forwards
Derivatives
Derivative notionals	31,473	30,510
Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Other derivative instruments, Trading derivatives | Equity contract options | Written or Sold
Derivatives
Derivative notionals	336,827	305,627
Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Other derivative instruments, Trading derivatives | Equity contract options | Purchased
Derivatives
Derivative notionals	303,265	275,216
Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Other derivative instruments, Trading derivatives | Commodity and other contracts
Derivatives
Derivative notionals	385,840	396,986
Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Other derivative instruments, Trading derivatives | Commodity and other contracts | Swaps
Derivatives
Derivative notionals	80,839	90,817
Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Other derivative instruments, Trading derivatives | Commodity and other contracts | Futures and forwards
Derivatives
Derivative notionals	108,241	106,021
Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Other derivative instruments, Trading derivatives | Commodity and other contract options | Written or Sold
Derivatives
Derivative notionals	103,276	104,581
Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Other derivative instruments, Trading derivatives | Commodity and other contract options | Purchased
Derivatives
Derivative notionals	93,484	95,567
Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Other derivative instruments, Trading derivatives | Credit derivatives
Derivatives
Derivative notionals	2,066,385	2,164,227
Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Other derivative instruments, Trading derivatives | Credit derivatives | Written or Sold
Derivatives
Derivative notionals	1,018,742	1,063,858
Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Other derivative instruments, Trading derivatives | Credit derivatives | Purchased
Derivatives
Derivative notionals	1,047,643	1,100,369
Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Other derivative instruments, Management hedges
Derivatives
Derivative notionals	123,745	131,014
Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Other derivative instruments, Management hedges | Interest rate contracts
Derivatives
Derivative notionals	77,733	83,073
Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Other derivative instruments, Management hedges | Interest rate contracts | Swaps
Derivatives
Derivative notionals	27,731	31,945
Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Other derivative instruments, Management hedges | Interest rate contracts | Futures and forwards
Derivatives
Derivative notionals	42,582	42,305
Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Other derivative instruments, Management hedges | Interest rate contract options | Written or Sold
Derivatives
Derivative notionals	3,695	3,913
Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Other derivative instruments, Management hedges | Interest rate contract options | Purchased
Derivatives
Derivative notionals	3,725	4,910
Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Other derivative instruments, Management hedges | Foreign exchange contracts
Derivatives
Derivative notionals	30,595	31,923
Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Other derivative instruments, Management hedges | Foreign exchange contracts | Swaps
Derivatives
Derivative notionals	24,257	23,990
Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Other derivative instruments, Management hedges | Foreign exchange contracts | Futures and forwards
Derivatives
Derivative notionals	5,472	7,069
Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Other derivative instruments, Management hedges | Foreign exchange contract options | Written or Sold
Derivatives
Derivative notionals	433	432
Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Other derivative instruments, Management hedges | Foreign exchange contract options | Purchased
Derivatives
Derivative notionals	433	432
Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Other derivative instruments, Management hedges | Equity contracts
Derivatives
Derivative notionals	0	0
Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Other derivative instruments, Management hedges | Equity contracts | Swaps
Derivatives
Derivative notionals	0	0
Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Other derivative instruments, Management hedges | Equity contracts | Futures and forwards
Derivatives
Derivative notionals	0	0
Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Other derivative instruments, Management hedges | Equity contract options | Written or Sold
Derivatives
Derivative notionals	0	0
Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Other derivative instruments, Management hedges | Equity contract options | Purchased
Derivatives
Derivative notionals	0	0
Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Other derivative instruments, Management hedges | Commodity and other contracts
Derivatives
Derivative notionals	0	0
Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Other derivative instruments, Management hedges | Commodity and other contracts | Swaps
Derivatives
Derivative notionals	0	0
Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Other derivative instruments, Management hedges | Commodity and other contracts | Futures and forwards
Derivatives
Derivative notionals	0	0
Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Other derivative instruments, Management hedges | Commodity and other contract options | Written or Sold
Derivatives
Derivative notionals	0	0
Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Other derivative instruments, Management hedges | Commodity and other contract options | Purchased
Derivatives
Derivative notionals	0	0
Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Other derivative instruments, Management hedges | Credit derivatives
Derivatives
Derivative notionals	15,417	16,018
Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Other derivative instruments, Management hedges | Credit derivatives | Written or Sold
Derivatives
Derivative notionals	0	0
Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Other derivative instruments, Management hedges | Credit derivatives | Purchased
Derivatives
Derivative notionals	$ 15,417	$ 16,018