DERIVATIVES ACTIVITIES - Derivative Notionals (Details) - USD ($)	Jun. 30, 2017	Dec. 31, 2016
Net Investment Hedging
Derivatives
Derivative notionals	$ 1,297,000,000	$ 1,825,000,000
Hedging instruments under ASC 815
Derivatives
Derivative notionals	266,841,000,000	227,616,000,000
Hedging instruments under ASC 815 | Interest rate contracts
Derivatives
Derivative notionals	185,356,000,000	151,428,000,000
Hedging instruments under ASC 815 | Interest rate swaps
Derivatives
Derivative notionals	185,341,000,000	151,331,000,000
Hedging instruments under ASC 815 | Interest rate futures and forwards
Derivatives
Derivative notionals	15,000,000	97,000,000
Hedging instruments under ASC 815 | Interest rate contract options | Written or Sold
Derivatives
Derivative notionals	0
Hedging instruments under ASC 815 | Interest rate contract options | Purchased
Derivatives
Derivative notionals	0	0
Hedging instruments under ASC 815 | Foreign exchange contracts
Derivatives
Derivative notionals	81,329,000,000	76,006,000,000
Hedging instruments under ASC 815 | Foreign exchange swaps
Derivatives
Derivative notionals	37,395,000,000	19,042,000,000
Hedging instruments under ASC 815 | Foreign exchange futures, forwards and spot
Derivatives
Derivative notionals	35,815,000,000	56,964,000,000
Hedging instruments under ASC 815 | Foreign exchange contract options | Written or Sold
Derivatives
Derivative notionals	1,447,000,000	0
Hedging instruments under ASC 815 | Foreign exchange contract options | Purchased
Derivatives
Derivative notionals	6,672,000,000	0
Hedging instruments under ASC 815 | Equity contracts
Derivatives
Derivative notionals	0	0
Hedging instruments under ASC 815 | Equity swaps
Derivatives
Derivative notionals	0	0
Hedging instruments under ASC 815 | Equity futures and forwards
Derivatives
Derivative notionals	0	0
Hedging instruments under ASC 815 | Equity contract options | Written or Sold
Derivatives
Derivative notionals	0	0
Hedging instruments under ASC 815 | Equity contract options | Purchased
Derivatives
Derivative notionals	0	0
Hedging instruments under ASC 815 | Commodity and other contracts
Derivatives
Derivative notionals	156,000,000	182,000,000
Hedging instruments under ASC 815 | Commodity and other swaps
Derivatives
Derivative notionals	0	0
Hedging instruments under ASC 815 | Commodity and other futures and forwards
Derivatives
Derivative notionals	156,000,000	182,000,000
Hedging instruments under ASC 815 | Commodity and other contracts | Written or Sold
Derivatives
Derivative notionals	0	0
Hedging instruments under ASC 815 | Commodity and other contracts | Purchased
Derivatives
Derivative notionals	0	0
Hedging instruments under ASC 815 | Credit derivatives
Derivatives
Derivative notionals	0	0
Hedging instruments under ASC 815 | Credit derivatives | Written or Sold
Derivatives
Derivative notionals	0	0
Hedging instruments under ASC 815 | Credit derivatives | Purchased
Derivatives
Derivative notionals	0	0
Other derivative instruments, Trading derivatives
Derivatives
Derivative notionals	53,338,681,000,000	45,753,242,000,000
Other derivative instruments, Trading derivatives | Interest rate contracts
Derivatives
Derivative notionals	36,869,516,000,000	31,699,124,000,000
Other derivative instruments, Trading derivatives | Interest rate swaps
Derivatives
Derivative notionals	22,079,797,000,000	19,145,250,000,000
Other derivative instruments, Trading derivatives | Interest rate futures and forwards
Derivatives
Derivative notionals	8,025,915,000,000	6,864,276,000,000
Other derivative instruments, Trading derivatives | Interest rate contract options | Written or Sold
Derivatives
Derivative notionals	3,433,889,000,000	2,921,070,000,000
Other derivative instruments, Trading derivatives | Interest rate contract options | Purchased
Derivatives
Derivative notionals	3,329,915,000,000	2,768,528,000,000
Other derivative instruments, Trading derivatives | Foreign exchange contracts
Derivatives
Derivative notionals	13,469,596,000,000	11,153,563,000,000
Other derivative instruments, Trading derivatives | Foreign exchange swaps
Derivatives
Derivative notionals	6,407,798,000,000	5,492,145,000,000
Other derivative instruments, Trading derivatives | Foreign exchange futures, forwards and spot
Derivatives
Derivative notionals	4,302,684,000,000	3,251,132,000,000
Other derivative instruments, Trading derivatives | Foreign exchange contract options | Written or Sold
Derivatives
Derivative notionals	1,375,250,000,000	1,194,325,000,000
Other derivative instruments, Trading derivatives | Foreign exchange contract options | Purchased
Derivatives
Derivative notionals	1,383,864,000,000	1,215,961,000,000
Other derivative instruments, Trading derivatives | Equity contracts
Derivatives
Derivative notionals	937,958,000,000	800,572,000,000
Other derivative instruments, Trading derivatives | Equity swaps
Derivatives
Derivative notionals	197,046,000,000	192,366,000,000
Other derivative instruments, Trading derivatives | Equity futures and forwards
Derivatives
Derivative notionals	46,582,000,000	37,557,000,000
Other derivative instruments, Trading derivatives | Equity contract options | Written or Sold
Derivatives
Derivative notionals	370,016,000,000	304,579,000,000
Other derivative instruments, Trading derivatives | Equity contract options | Purchased
Derivatives
Derivative notionals	324,314,000,000	266,070,000,000
Other derivative instruments, Trading derivatives | Commodity and other contracts
Derivatives
Derivative notionals	359,636,000,000	357,560,000,000
Other derivative instruments, Trading derivatives | Commodity and other swaps
Derivatives
Derivative notionals	68,690,000,000	70,774,000,000
Other derivative instruments, Trading derivatives | Commodity and other futures and forwards
Derivatives
Derivative notionals	153,554,000,000	142,530,000,000
Other derivative instruments, Trading derivatives | Commodity and other contracts | Written or Sold
Derivatives
Derivative notionals	69,294,000,000	74,627,000,000
Other derivative instruments, Trading derivatives | Commodity and other contracts | Purchased
Derivatives
Derivative notionals	68,098,000,000	69,629,000,000
Other derivative instruments, Trading derivatives | Credit derivatives
Derivatives
Derivative notionals	1,701,975,000,000	1,742,423,000,000
Other derivative instruments, Trading derivatives | Credit derivatives | Written or Sold
Derivatives
Derivative notionals	845,028,000,000	859,420,000,000
Other derivative instruments, Trading derivatives | Credit derivatives | Purchased
Derivatives
Derivative notionals	856,947,000,000	883,003,000,000
Other derivative instruments, Management hedges
Derivatives
Derivative notionals	117,959,000,000	135,802,000,000
Other derivative instruments, Management hedges | Interest rate contracts
Derivatives
Derivative notionals	71,841,000,000	90,237,000,000
Other derivative instruments, Management hedges | Interest rate swaps
Derivatives
Derivative notionals	53,242,000,000	47,324,000,000
Other derivative instruments, Management hedges | Interest rate futures and forwards
Derivatives
Derivative notionals	14,447,000,000	30,834,000,000
Other derivative instruments, Management hedges | Interest rate contract options | Written or Sold
Derivatives
Derivative notionals	1,822,000,000	4,759,000,000
Other derivative instruments, Management hedges | Interest rate contract options | Purchased
Derivatives
Derivative notionals	2,330,000,000	7,320,000,000
Other derivative instruments, Management hedges | Foreign exchange contracts
Derivatives
Derivative notionals	31,951,000,000	26,095,000,000
Other derivative instruments, Management hedges | Foreign exchange swaps
Derivatives
Derivative notionals	26,221,000,000	22,676,000,000
Other derivative instruments, Management hedges | Foreign exchange futures, forwards and spot
Derivatives
Derivative notionals	5,730,000,000	3,419,000,000
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	14,167,000,000	19,470,000,000
Other derivative instruments, Management hedges | Credit derivatives | Written or Sold
Derivatives
Derivative notionals	64,000,000	0
Other derivative instruments, Management hedges | Credit derivatives | Purchased
Derivatives
Derivative notionals	$ 14,103,000,000	$ 19,470,000,000