DEBT - Deferred Gain and Issuance Costs (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Deferred Gain and Issuance Costs [Abstract]
Deferred gain	$ 211	$ 313
Deferred issuance costs and original issue discounts	(65)	(97)
Net deferred gain and issuance costs	$ 146	$ 216