GOODWILL AND OTHER INTANGIBLE ASSETS - Summary of Amortization Expense (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Finite-Lived Intangible Assets [Line Items]
Amortization of intangibles	$ 100	$ 100	$ 300	$ 320
Other intangible assets, excluding software
Finite-Lived Intangible Assets [Line Items]
Amortization of intangibles	100	100	300	320
Software
Finite-Lived Intangible Assets [Line Items]
Amortization of intangibles	$ 24	$ 23	$ 72	$ 70