DERIVATIVES ACTIVITIES - Derivative Notionals (Details) - USD ($) $ in Millions	Sep. 30, 2016	Dec. 31, 2015
Net Investment Hedging
Derivatives
Derivative notionals	$ 1,991	$ 2,102
Hedging instruments under ASC 815 (SFAS 133)
Derivatives
Derivative notionals	301,995	263,763
Hedging instruments under ASC 815 (SFAS 133) | Interest rate contracts
Derivatives
Derivative notionals	214,277	166,576
Hedging instruments under ASC 815 (SFAS 133) | Interest rate swaps
Derivatives
Derivative notionals	213,863	166,576
Hedging instruments under ASC 815 (SFAS 133) | Interest rate futures and forwards
Derivatives
Derivative notionals	414	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	86,827	96,398
Hedging instruments under ASC 815 (SFAS 133) | Foreign exchange swaps
Derivatives
Derivative notionals	21,410	23,007
Hedging instruments under ASC 815 (SFAS 133) | Foreign exchange futures, forwards and spot
Derivatives
Derivative notionals	65,417	72,124
Hedging instruments under ASC 815 (SFAS 133) | Foreign exchange contract options | Written or Sold
Derivatives
Derivative notionals	0	448
Hedging instruments under ASC 815 (SFAS 133) | Foreign exchange contract options | Purchased
Derivatives
Derivative notionals	0	819
Hedging instruments under ASC 815 (SFAS 133) | Equity contracts
Derivatives
Derivative notionals	0	0
Hedging instruments under ASC 815 (SFAS 133) | Equity swaps
Derivatives
Derivative notionals	0	0
Hedging instruments under ASC 815 (SFAS 133) | Equity 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	891	789
Hedging instruments under ASC 815 (SFAS 133) | Commodity and other swaps
Derivatives
Derivative notionals	0	0
Hedging instruments under ASC 815 (SFAS 133) | Commodity and other futures and forwards
Derivatives
Derivative notionals	891	789
Hedging instruments under ASC 815 (SFAS 133) | Commodity and other contracts | Written or Sold
Derivatives
Derivative notionals	0	0
Hedging instruments under ASC 815 (SFAS 133) | Commodity and other contracts | 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
Other derivative instruments, Trading derivatives
Derivatives
Derivative notionals	48,682,596	47,612,050
Other derivative instruments, Trading derivatives | Interest rate contracts
Derivatives
Derivative notionals	33,384,423	34,998,356
Other derivative instruments, Trading derivatives | Interest rate swaps
Derivatives
Derivative notionals	20,853,766	22,208,794
Other derivative instruments, Trading derivatives | Interest rate futures and forwards
Derivatives
Derivative notionals	6,451,502	6,868,340
Other derivative instruments, Trading derivatives | Interest rate contract options | Written or Sold
Derivatives
Derivative notionals	3,138,417	3,033,617
Other derivative instruments, Trading derivatives | Interest rate contract options | Purchased
Derivatives
Derivative notionals	2,940,738	2,887,605
Other derivative instruments, Trading derivatives | Foreign exchange contracts
Derivatives
Derivative notionals	11,947,243	9,586,816
Other derivative instruments, Trading derivatives | Foreign exchange swaps
Derivatives
Derivative notionals	5,954,717	4,765,687
Other derivative instruments, Trading derivatives | Foreign exchange futures, forwards and spot
Derivatives
Derivative notionals	3,410,229	2,563,649
Other derivative instruments, Trading derivatives | Foreign exchange contract options | Written or Sold
Derivatives
Derivative notionals	1,271,307	1,125,664
Other derivative instruments, Trading derivatives | Foreign exchange contract options | Purchased
Derivatives
Derivative notionals	1,310,990	1,131,816
Other derivative instruments, Trading derivatives | Equity contracts
Derivatives
Derivative notionals	924,678	778,636
Other derivative instruments, Trading derivatives | Equity swaps
Derivatives
Derivative notionals	195,000	180,963
Other derivative instruments, Trading derivatives | Equity futures and forwards
Derivatives
Derivative notionals	39,964	33,735
Other derivative instruments, Trading derivatives | Equity contract options | Written or Sold
Derivatives
Derivative notionals	364,514	298,876
Other derivative instruments, Trading derivatives | Equity contract options | Purchased
Derivatives
Derivative notionals	325,200	265,062
Other derivative instruments, Trading derivatives | Commodity and other contracts
Derivatives
Derivative notionals	353,988	315,734
Other derivative instruments, Trading derivatives | Commodity and other swaps
Derivatives
Derivative notionals	61,882	70,561
Other derivative instruments, Trading derivatives | Commodity and other futures and forwards
Derivatives
Derivative notionals	149,604	106,474
Other derivative instruments, Trading derivatives | Commodity and other contracts | Written or Sold
Derivatives
Derivative notionals	73,673	72,648
Other derivative instruments, Trading derivatives | Commodity and other contracts | Purchased
Derivatives
Derivative notionals	68,829	66,051
Other derivative instruments, Trading derivatives | Credit derivatives
Derivatives
Derivative notionals	2,072,264	1,932,508
Other derivative instruments, Trading derivatives | Credit derivatives | Written or Sold
Derivatives
Derivative notionals	1,021,118	950,922
Other derivative instruments, Trading derivatives | Credit derivatives | Purchased
Derivatives
Derivative notionals	1,051,146	981,586
Other derivative instruments, Management hedges
Derivatives
Derivative notionals	134,839	125,193
Other derivative instruments, Management hedges | Interest rate contracts
Derivatives
Derivative notionals	81,687	74,571
Other derivative instruments, Management hedges | Interest rate swaps
Derivatives
Derivative notionals	39,537	28,969
Other derivative instruments, Management hedges | Interest rate futures and forwards
Derivatives
Derivative notionals	34,147	38,421
Other derivative instruments, Management hedges | Interest rate contract options | Written or Sold
Derivatives
Derivative notionals	4,653	2,606
Other derivative instruments, Management hedges | Interest rate contract options | Purchased
Derivatives
Derivative notionals	3,350	4,575
Other derivative instruments, Management hedges | Foreign exchange contracts
Derivatives
Derivative notionals	25,352	26,994
Other derivative instruments, Management hedges | Foreign exchange swaps
Derivatives
Derivative notionals	22,272	23,960
Other derivative instruments, Management hedges | Foreign exchange futures, forwards and spot
Derivatives
Derivative notionals	3,080	3,034
Other derivative instruments, Management hedges | Foreign exchange contract options | Written or Sold
Derivatives
Derivative notionals	0	0
Other derivative instruments, Management hedges | Foreign exchange contract options | Purchased
Derivatives
Derivative notionals	0	0
Other derivative instruments, Management hedges | Equity contracts
Derivatives
Derivative notionals	0	0
Other derivative instruments, Management hedges | Equity swaps
Derivatives
Derivative notionals	0	0
Other derivative instruments, Management hedges | Equity futures and forwards
Derivatives
Derivative notionals	0	0
Other derivative instruments, Management hedges | Equity contract options | Written or Sold
Derivatives
Derivative notionals	0	0
Other derivative instruments, Management hedges | Equity contract options | Purchased
Derivatives
Derivative notionals	0	0
Other derivative instruments, Management hedges | Commodity and other contracts
Derivatives
Derivative notionals	0	0
Other derivative instruments, Management hedges | Commodity and other swaps
Derivatives
Derivative notionals	0	0
Other derivative instruments, Management hedges | Commodity and other futures and forwards
Derivatives
Derivative notionals	0	0
Other derivative instruments, Management hedges | Commodity and other contracts | Written or Sold
Derivatives
Derivative notionals	0	0
Other derivative instruments, Management hedges | Commodity and other contracts | Purchased
Derivatives
Derivative notionals	0	0
Other derivative instruments, Management hedges | Credit derivatives
Derivatives
Derivative notionals	27,800	23,628
Other derivative instruments, Management hedges | Credit derivatives | Written or Sold
Derivatives
Derivative notionals	0	0
Other derivative instruments, Management hedges | Credit derivatives | Purchased
Derivatives
Derivative notionals	$ 27,800	$ 23,628