DERIVATIVES - Schedule of Derivative Instruments (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Derivative Assets
Derivative assets	$ 597	$ 449
Less: Gross amounts offset in the Consolidated Balance Sheets	(78)	(87)
Less: Cash collateral applied	(54)	(45)
Total net derivative fair values presented in the Consolidated Balance Sheets	465	317
Derivative Liabilities
Derivative Liabilities	294	415
Less: Gross amounts offset in the Consolidated Balance Sheets	(78)	(87)
Less: Cash collateral applied	(43)	(36)
Total net derivative fair values presented in the Consolidated Balance Sheets	173	292
Derivatives not designated as hedging instruments:
Derivative Assets
Derivative assets	597	444
Derivative Liabilities
Derivative Liabilities	279	415
Interest rate contracts
Derivative Assets
Derivative assets	443	306
Derivative Liabilities
Derivative Liabilities	160	277
Interest rate contracts \| Derivatives designated as hedging instruments:
Derivatives, Fair Value [Line Items]
Notional amount	14,500	12,050
Derivative Assets
Derivative assets	0	5
Derivative Liabilities
Derivative Liabilities	15	0
Interest rate contracts \| Derivatives not designated as hedging instruments:
Derivatives, Fair Value [Line Items]
Notional amount	126,525	117,076
Derivative Assets
Derivative assets	443	301
Derivative Liabilities
Derivative Liabilities	145	277
Foreign exchange contracts
Derivative Assets
Derivative assets	135	129
Derivative Liabilities
Derivative Liabilities	113	113
Foreign exchange contracts \| Derivatives not designated as hedging instruments:
Derivatives, Fair Value [Line Items]
Notional amount	11,858	9,866
Derivative Assets
Derivative assets	135	129
Derivative Liabilities
Derivative Liabilities	113	113
Other contracts
Derivative Assets
Derivative assets	19	14
Derivative Liabilities
Derivative Liabilities	21	25
Other contracts \| Derivatives not designated as hedging instruments:
Derivatives, Fair Value [Line Items]
Notional amount	5,221	3,555
Derivative Assets
Derivative assets	19	14
Derivative Liabilities
Derivative Liabilities	$ 21	$ 25

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

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