BASIS OF PRESENTATION (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended		36 Months Ended
	Jan. 01, 2020	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Jan. 01, 2025	Dec. 31, 2019
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Retained earnings		$ 6,068		$ 6,068			$ 6,498
Income tax expense		$ 54	$ 127	$ 65	$ 254
Accounting Standards Update 2016-13
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Basis point change in CET1	(0.22%)
Scenario, Forecast | Accounting Standards Update 2016-13
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Basis point change in CET1						(0.06%)
Capital impact phase in percentage						25.00%
Cumulative Effect, Period Of Adoption, Adjustment | Accounting Standards Update 2016-13
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Retained earnings	$ (337)
Income tax expense	(114)
Allowance for credit loss	$ 451