SEGMENT INFORMATION - Geographic Information, Revenue (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Revenues and long-lived assets by geographic region
Revenue	$ 2,224	$ 2,209	$ 2,152	$ 2,016	$ 2,121	$ 2,136	$ 2,128	$ 1,995	$ 8,601	$ 8,380	$ 8,724
U.S. and Puerto Rico
Revenues and long-lived assets by geographic region
Revenue									5,164	5,011	5,225
China
Revenues and long-lived assets by geographic region
Revenue									368	361	331
Canada
Revenues and long-lived assets by geographic region
Revenue									339	319	326
Japan
Revenues and long-lived assets by geographic region
Revenue									241	226	223
Poland
Revenues and long-lived assets by geographic region
Revenue									231	218	201
Mexico
Revenues and long-lived assets by geographic region
Revenue									228	211	201
Egypt
Revenues and long-lived assets by geographic region
Revenue									218	178	152
France
Revenues and long-lived assets by geographic region
Revenue									201	205	188
Russia
Revenues and long-lived assets by geographic region
Revenue									180	154	200
Germany
Revenues and long-lived assets by geographic region
Revenue									150	170	157
United Kingdom
Revenues and long-lived assets by geographic region
Revenue									115	117	108
Spain
Revenues and long-lived assets by geographic region
Revenue									86	83	77
Italy
Revenues and long-lived assets by geographic region
Revenue									85	85	78
Other
Revenues and long-lived assets by geographic region
Revenue									$ 995	$ 1,042	$ 1,257