GUARANTEES AND COMMITMENTS - Guarantees (Details) - USD ($) $ in Millions	Sep. 30, 2016	Dec. 31, 2015
Maximum potential amount of future payments
Expire within 1 year	$ 205,300	$ 198,000
Expire after 1 year	200,300	203,900
Total amount outstanding	405,600	401,900
Carrying value	1,420	2,027
Fair value of securities in trusts funded by reinsurer relating to indemnification	7,400	6,300
Cash collateral available to reimburse losses realized under guarantees and indemnifications	52,000	52,000
Securities and other marketable assets held as collateral, the majority of which collateral is held to reimburse losses realized under securities lending indemnifications	37,000	33,000
Letters of credit in favor of the Company held as collateral	4,100	4,200
Investment grade
Maximum potential amount of future payments
Total amount outstanding	122,000	127,400
Non-investment grade
Maximum potential amount of future payments
Total amount outstanding	18,300	19,600
Not rated
Maximum potential amount of future payments
Total amount outstanding	265,300	254,900
Financial standby letters of credit
Maximum potential amount of future payments
Expire within 1 year	25,800	23,800
Expire after 1 year	69,300	73,000
Total amount outstanding	95,100	96,800
Carrying value	170	152
Financial standby letters of credit | Investment grade
Maximum potential amount of future payments
Total amount outstanding	68,400	69,200
Financial standby letters of credit | Non-investment grade
Maximum potential amount of future payments
Total amount outstanding	14,100	15,400
Financial standby letters of credit | Not rated
Maximum potential amount of future payments
Total amount outstanding	12,600	12,200
Performance guarantees
Maximum potential amount of future payments
Expire within 1 year	7,700	7,400
Expire after 1 year	3,800	4,100
Total amount outstanding	11,500	11,500
Carrying value	19	23
Performance guarantees | Investment grade
Maximum potential amount of future payments
Total amount outstanding	6,500	6,600
Performance guarantees | Non-investment grade
Maximum potential amount of future payments
Total amount outstanding	4,100	4,100
Performance guarantees | Not rated
Maximum potential amount of future payments
Total amount outstanding	900	800
Derivative instruments deemed to be guarantees
Maximum potential amount of future payments
Expire within 1 year	4,500	3,600
Expire after 1 year	78,400	74,900
Total amount outstanding	82,900	78,500
Carrying value	954	1,779
Derivative instruments deemed to be guarantees | Investment grade
Maximum potential amount of future payments
Total amount outstanding	0	0
Derivative instruments deemed to be guarantees | Non-investment grade
Maximum potential amount of future payments
Total amount outstanding	0	0
Derivative instruments deemed to be guarantees | Not rated
Maximum potential amount of future payments
Total amount outstanding	82,900	78,500
Loans sold with recourse
Maximum potential amount of future payments
Expire within 1 year	0	0
Expire after 1 year	200	200
Total amount outstanding	200	200
Carrying value	13	17
Repurchase reserve for Consumer mortgages representations and warranties	114	152
Loans sold with recourse | Investment grade
Maximum potential amount of future payments
Total amount outstanding	0	0
Loans sold with recourse | Non-investment grade
Maximum potential amount of future payments
Total amount outstanding	0	0
Loans sold with recourse | Not rated
Maximum potential amount of future payments
Total amount outstanding	200	200
Securities lending indemnifications
Maximum potential amount of future payments
Expire within 1 year	83,900	79,000
Expire after 1 year	0	0
Total amount outstanding	83,900	79,000
Carrying value	0	0
Securities lending indemnifications | Investment grade
Maximum potential amount of future payments
Total amount outstanding	0	0
Securities lending indemnifications | Non-investment grade
Maximum potential amount of future payments
Total amount outstanding	0	0
Securities lending indemnifications | Not rated
Maximum potential amount of future payments
Total amount outstanding	83,900	79,000
Credit card merchant processing
Maximum potential amount of future payments
Expire within 1 year	83,300	84,200
Expire after 1 year	0	0
Total amount outstanding	83,300	84,200
Carrying value	0	0
Credit card merchant processing | Investment grade
Maximum potential amount of future payments
Total amount outstanding	0	0
Credit card merchant processing | Non-investment grade
Maximum potential amount of future payments
Total amount outstanding	0	0
Credit card merchant processing | Not rated
Maximum potential amount of future payments
Total amount outstanding	83,300	84,200
Credit card arrangements with partners
Maximum potential amount of future payments
Expire within 1 year	0
Expire after 1 year	1,500
Total amount outstanding	1,500
Carrying value	206
Credit card arrangements with partners | Investment grade
Maximum potential amount of future payments
Total amount outstanding	0
Credit card arrangements with partners | Non-investment grade
Maximum potential amount of future payments
Total amount outstanding	0
Credit card arrangements with partners | Not rated
Maximum potential amount of future payments
Total amount outstanding	1,500
Custody indemnifications and other
Maximum potential amount of future payments
Expire within 1 year	100	0
Expire after 1 year	47,100	51,700
Total amount outstanding	47,200	51,700
Carrying value	58	56
Custody indemnifications and other | Investment grade
Maximum potential amount of future payments
Total amount outstanding	47,100	51,600
Custody indemnifications and other | Non-investment grade
Maximum potential amount of future payments
Total amount outstanding	100	100
Custody indemnifications and other | Not rated
Maximum potential amount of future payments
Total amount outstanding	0	0
Futures and over-the-counter derivatives clearing
Maximum potential amount of future payments
Amount of cash initial margin collected and remitted	$ 6,000	$ 4,300