DERIVATIVES ACTIVITIES - Credit Derivatives (Details) $ in Millions	6 Months Ended
	Jun. 30, 2017 USD ($) agency	Dec. 31, 2016 USD ($)
Credit Risk Derivatives
Fair values, Receivable	$ 23,981	$ 24,821
Fair Values, Payable	25,446	25,825
Notionals, Protection purchased	871,050	902,473
Notionals, Protection sold	845,092	859,420
Fair value of derivative in liability position	32,000	26,000
Fair value of collateral already posted	$ 28,000	26,000
Number of rating agencies | agency	3
Additional collateral to be posted	$ 700
Collateral to be segregated	300
Aggregate cash obligations and collateral requirements	1,000
Purchased
Credit Risk Derivatives
Fair values, Receivable	5,882	9,077
Fair Values, Payable	19,750	17,110
Sold
Credit Risk Derivatives
Fair values, Receivable	18,099	15,744
Fair Values, Payable	5,696	8,715
Within 1 year
Credit Risk Derivatives
Fair values, Receivable	3,234	4,113
Fair Values, Payable	4,172	4,841
Notionals, Protection purchased	282,692	293,059
Notionals, Protection sold	281,166	287,262
From 1 to 5 years
Credit Risk Derivatives
Fair values, Receivable	18,284	17,735
Fair Values, Payable	18,452	17,986
Notionals, Protection purchased	539,944	551,155
Notionals, Protection sold	522,198	523,371
After 5 years
Credit Risk Derivatives
Fair values, Receivable	2,463	2,973
Fair Values, Payable	2,822	2,998
Notionals, Protection purchased	48,414	58,259
Notionals, Protection sold	41,728	48,787
Investment grade
Credit Risk Derivatives
Fair values, Receivable	10,740	9,605
Fair Values, Payable	10,839	9,995
Notionals, Protection purchased	654,355	675,138
Notionals, Protection sold	642,096	648,247
Non-investment grade
Credit Risk Derivatives
Fair values, Receivable	13,241	15,216
Fair Values, Payable	14,607	15,830
Notionals, Protection purchased	216,695	227,335
Notionals, Protection sold	202,996	211,173
Credit default swaps and options
Credit Risk Derivatives
Fair values, Receivable	23,582	24,502
Fair Values, Payable	23,970	24,631
Notionals, Protection purchased	844,661	883,719
Notionals, Protection sold	835,627	852,900
Total return swaps and other
Credit Risk Derivatives
Fair values, Receivable	399	319
Fair Values, Payable	1,476	1,194
Notionals, Protection purchased	26,389	18,754
Notionals, Protection sold	9,465	6,520
Banks
Credit Risk Derivatives
Fair values, Receivable	10,015	11,895
Fair Values, Payable	9,077	10,930
Notionals, Protection purchased	336,802	407,992
Notionals, Protection sold	352,533	414,720
Broker-dealers
Credit Risk Derivatives
Fair values, Receivable	3,030	3,536
Fair Values, Payable	3,252	3,952
Notionals, Protection purchased	91,096	115,013
Notionals, Protection sold	100,526	119,810
Non-financial
Credit Risk Derivatives
Fair values, Receivable	68	82
Fair Values, Payable	78	99
Notionals, Protection purchased	3,798	4,014
Notionals, Protection sold	1,561	2,061
Insurance and other financial institutions
Credit Risk Derivatives
Fair values, Receivable	10,868	9,308
Fair Values, Payable	13,039	10,844
Notionals, Protection purchased	439,354	375,454
Notionals, Protection sold	390,472	$ 322,829
Interest rate swaps
Credit Risk Derivatives
Cash proceeds received for assets derecognized	2,100
Fair value of derecognized assets	2,300
Fair value gross derivative assets	14
Trading derivatives, liability	$ 28