DERIVATIVES - Schedule of Derivative Instruments (Details) - USD ($) $ in Millions		Jun. 30, 2017		Dec. 31, 2016
Derivative Assets
Derivative assets		$ 484	[1],[2]	$ 759
Less: Gross amounts offset in the Consolidated Balance Sheets	[3]	(70)	[1]	(106)
Less: Cash collateral applied	[3]	(6)	[1]	(26)
Total net derivative fair values presented in the Consolidated Balance Sheets		408	[1]	627
Derivative Liabilities
Derivative Liabilities		403	[1],[2]	778
Less: Gross amounts offset in the Consolidated Balance Sheets	[3]	(70)	[1]	(106)
Less: Cash collateral applied	[3]	(174)	[1]	(13)
Total net derivative fair values presented in the Consolidated Balance Sheets		159	[1]	659
Derivatives not designated as hedging instruments:
Derivative Assets
Derivative assets		480	[1]	707
Derivative Liabilities
Derivative Liabilities		400	[1]	585
Interest rate swaps
Derivative Assets
Derivative assets		341	[2]	609
Derivative Liabilities
Derivative Liabilities		277	[2]	645
Interest rate swaps | Derivatives designated as hedging instruments:
Derivatives, Fair Value [Line Items]
Notional amount	[4]	16,800		13,350
Derivative Assets
Derivative assets		4	[1]	52
Derivative Liabilities
Derivative Liabilities		3	[1]	193
Interest rate swaps | Derivatives not designated as hedging instruments:
Derivatives, Fair Value [Line Items]
Notional amount	[4]	65,980		54,656
Derivative Assets
Derivative assets		337	[1]	557
Derivative Liabilities
Derivative Liabilities		274	[1]	452
Foreign exchange contracts
Derivative Assets
Derivative assets		132	[2]	134
Derivative Liabilities
Derivative Liabilities		121	[2]	126
Foreign exchange contracts | Derivatives not designated as hedging instruments:
Derivatives, Fair Value [Line Items]
Notional amount	[4]	10,120		8,039
Derivative Assets
Derivative assets		132	[1]	134
Derivative Liabilities
Derivative Liabilities		121	[1]	126
Other contracts
Derivative Assets
Derivative assets		11	[2]	16
Derivative Liabilities
Derivative Liabilities		5	[2]	7
Other contracts | Derivatives not designated as hedging instruments:
Derivatives, Fair Value [Line Items]
Notional amount	[4]	1,380		1,498
Derivative Assets
Derivative assets		11	[1]	16
Derivative Liabilities
Derivative Liabilities		$ 5	[1]	$ 7

[1] Amounts reflect variation margin payments that are characterized as settlement per the rules of the Company’s central counterparties that became effective January 3, 2017.

[2] Amounts reflect variation margin payments that are characterized as settlement per the rules of the Company’s central counterparties that became effective January 3, 2017.

[3] Amounts represent the impact of legally enforceable master netting agreements that allow the Company to settle positive and negative positions.

[4] The notional or contractual amount of interest rate derivatives and foreign exchange contracts is the amount upon which interest and other payments under the contract are based. Notional amounts are typically not exchanged. Therefore, notional amounts should not be taken as the measure of credit or market risk, as they do not measure the true economic risk of these contracts.