DERIVATIVES ACTIVITIES - Credit Derivatives (Details) $ in Millions	6 Months Ended
	Jun. 30, 2015 USD ($) counterparty agency	Dec. 31, 2014 USD ($)
Credit Derivative
Percentage of receivables from counterparties with collateral agreements	98.00%	98.00%
Number of top counterparties which are banks, financial institutions, and other dealers | counterparty	15
Fair value, Receivable	$ 39,362	$ 43,796
Fair Value, Payable	39,610	43,985
Notionals, Protection Purchased	1,224,696	1,116,387
Notionals, Protection Sold	1,171,760	1,063,858
Fair value of derivative in liability position	24,000	30,000
Fair value of collateral already posted	$ 21,000	27,000
Number of rating agencies | agency	3
Additional collateral to be posted	$ 2,000
Collateral to be segregated	100
Aggregate cash obligations and collateral requirements	2,100
Purchased
Credit Derivative
Fair value, Receivable	14,100	18,708
Fair Value, Payable	26,473	26,527
Sold
Credit Derivative
Fair value, Receivable	25,262	25,088
Fair Value, Payable	13,137	17,458
Within 1 year
Credit Derivative
Fair value, Receivable	2,697	4,356
Fair Value, Payable	2,567	4,278
Notionals, Protection Purchased	253,344	250,489
Notionals, Protection Sold	234,619	229,502
From 1 to 5 years
Credit Derivative
Fair value, Receivable	32,104	34,692
Fair Value, Payable	32,636	35,160
Notionals, Protection Purchased	890,348	790,251
Notionals, Protection Sold	866,199	772,001
After 5 years
Credit Derivative
Fair value, Receivable	4,561	4,748
Fair Value, Payable	4,407	4,547
Notionals, Protection Purchased	81,004	75,647
Notionals, Protection Sold	70,942	62,355
Investment Grade
Credit Derivative
Fair value, Receivable	15,813	17,432
Fair Value, Payable	15,786	17,182
Notionals, Protection Purchased	936,496	824,831
Notionals, Protection Sold	894,935	786,848
Non-Investment Grade
Credit Derivative
Fair value, Receivable	23,549	26,364
Fair Value, Payable	23,824	26,803
Notionals, Protection Purchased	288,200	291,556
Notionals, Protection Sold	276,825	277,010
Credit default swaps and options
Credit Derivative
Fair value, Receivable	39,053	42,930
Fair Value, Payable	38,320	42,201
Notionals, Protection Purchased	1,205,705	1,094,199
Notionals, Protection Sold	1,167,390	1,054,671
Total return swaps and other
Credit Derivative
Fair value, Receivable	309	866
Fair Value, Payable	1,290	1,784
Notionals, Protection Purchased	18,991	22,188
Notionals, Protection Sold	4,370	9,187
Bank
Credit Derivative
Fair value, Receivable	19,211	24,828
Fair Value, Payable	17,471	23,189
Notionals, Protection Purchased	580,952	574,764
Notionals, Protection Sold	576,798	604,700
Broker-dealer
Credit Derivative
Fair value, Receivable	6,891	8,093
Fair Value, Payable	7,565	9,309
Notionals, Protection Purchased	195,843	204,542
Notionals, Protection Sold	193,676	199,693
Non-financial
Credit Derivative
Fair value, Receivable	86	91
Fair Value, Payable	300	113
Notionals, Protection Purchased	4,039	3,697
Notionals, Protection Sold	1,577	1,595
Insurance and other financial institutions
Credit Derivative
Fair value, Receivable	13,174	10,784
Fair Value, Payable	14,274	11,374
Notionals, Protection Purchased	443,862	333,384
Notionals, Protection Sold	399,709	$ 257,870
Interest Rate Swap [Member]
Credit Derivative
Amount derecognized	2,200
Cash proceeds received for assets derecognized	2,200
Fair value of derecognized assets	2,100
Fair value gross derivative assets	17
Trading derivatives, liability	$ 71