DERIVATIVES - Schedule of Derivative Instruments (Details) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
Derivative Assets
Derivative assets	$ 969	$ 449
Less: Gross amounts offset in the Consolidated Balance Sheets	(83)	(87)
Less: Cash collateral applied	(53)	(45)
Total net derivative fair values presented in the Consolidated Balance Sheets	833	317
Derivative Liabilities
Derivative Liabilities	280	415
Less: Gross amounts offset in the Consolidated Balance Sheets	(83)	(87)
Less: Cash collateral applied	(91)	(36)
Total net derivative fair values presented in the Consolidated Balance Sheets	106	292
Derivatives not designated as hedging instruments:
Derivative Assets
Derivative assets	969	444
Derivative Liabilities
Derivative Liabilities	277	415
Interest rate contracts
Derivative Assets
Derivative assets	808	306
Derivative Liabilities
Derivative Liabilities	130	277
Interest rate contracts \| Derivatives designated as hedging instruments:
Derivatives, Fair Value [Line Items]
Notional amount	25,096	12,050
Derivative Assets
Derivative assets	0	5
Derivative Liabilities
Derivative Liabilities	3	0
Interest rate contracts \| Derivatives not designated as hedging instruments:
Derivatives, Fair Value [Line Items]
Notional amount	133,570	117,076
Derivative Assets
Derivative assets	808	301
Derivative Liabilities
Derivative Liabilities	127	277
Foreign exchange contracts
Derivative Assets
Derivative assets	132	129
Derivative Liabilities
Derivative Liabilities	116	113
Foreign exchange contracts \| Derivatives not designated as hedging instruments:
Derivatives, Fair Value [Line Items]
Notional amount	13,431	9,866
Derivative Assets
Derivative assets	132	129
Derivative Liabilities
Derivative Liabilities	116	113
Other contracts
Derivative Assets
Derivative assets	29	14
Derivative Liabilities
Derivative Liabilities	34	25
Other contracts \| Derivatives not designated as hedging instruments:
Derivatives, Fair Value [Line Items]
Notional amount	8,040	3,555
Derivative Assets
Derivative assets	29	14
Derivative Liabilities
Derivative Liabilities	$ 34	$ 25

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

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