REVENUE RECOGNITION Disaggregation of Revenue (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Disaggregation of Revenue [Line Items]
Net sales	[1]	$ 5,714	$ 5,123	$ 16,693	$ 15,341
Consolidation, Eliminations
Disaggregation of Revenue [Line Items]
Net sales	[1]	52	48	143	150
Intersegment Eliminations [Member]
Disaggregation of Revenue [Line Items]
Net sales		(31)	(32)	(95)	(95)
North American Industrial Packaging
Disaggregation of Revenue [Line Items]
Net sales		3,738	3,351	10,810	9,947
EMEA Industrial Packaging
Disaggregation of Revenue [Line Items]
Net sales		331	306	1,121	953
Brazilian Industrial Packaging
Disaggregation of Revenue [Line Items]
Net sales			52		148
European Coated Paperboard
Disaggregation of Revenue [Line Items]
Net sales		52	90	252	266
Global Cellulose Fibers
Disaggregation of Revenue [Line Items]
Net sales		729	564	1,981	1,737
North American Printing Papers
Disaggregation of Revenue [Line Items]
Net sales		425	362	1,201	1,073
Brazilian Papers
Disaggregation of Revenue [Line Items]
Net sales		200	150	557	434
European Papers
Disaggregation of Revenue [Line Items]
Net sales		218	232	723	728
United States
Disaggregation of Revenue [Line Items]
Net sales	[1]	4,612	4,054	13,141	12,086
United States | Consolidation, Eliminations
Disaggregation of Revenue [Line Items]
Net sales	[1]	50	44	139	146
EMEA
Disaggregation of Revenue [Line Items]
Net sales	[1]	683	694	2,339	2,142
EMEA | Consolidation, Eliminations
Disaggregation of Revenue [Line Items]
Net sales	[1]	(1)	(3)	(6)	(11)
Pacific Rim and Asia
Disaggregation of Revenue [Line Items]
Net sales	[1]	60	57	169	138
Pacific Rim and Asia | Consolidation, Eliminations
Disaggregation of Revenue [Line Items]
Net sales	[1]	3	10	10	20
Americas, other than U.S.
Disaggregation of Revenue [Line Items]
Net sales	[1]	359	318	1,044	975
Americas, other than U.S. | Consolidation, Eliminations
Disaggregation of Revenue [Line Items]
Net sales	[1]	0	(3)	0	(5)
Industrial Packaging
Disaggregation of Revenue [Line Items]
Net sales		4,087	3,768	12,096	11,220
Industrial Packaging | Geography Eliminations [Member]
Disaggregation of Revenue [Line Items]
Net sales	[1]	4,087	3,768	12,096	11,220
Industrial Packaging | Operating Segments [Member]
Disaggregation of Revenue [Line Items]
Net sales		4,087	3,768	12,096	11,220
Industrial Packaging | Intersegment Eliminations [Member]
Disaggregation of Revenue [Line Items]
Net sales		(34)	(31)	(87)	(94)
Industrial Packaging | North American Industrial Packaging
Disaggregation of Revenue [Line Items]
Net sales		3,738	3,351	10,810	9,947
Industrial Packaging | EMEA Industrial Packaging
Disaggregation of Revenue [Line Items]
Net sales		331	306	1,121	953
Industrial Packaging | Brazilian Industrial Packaging
Disaggregation of Revenue [Line Items]
Net sales			52		148
Industrial Packaging | European Coated Paperboard
Disaggregation of Revenue [Line Items]
Net sales		52	90	252	266
Industrial Packaging | United States
Disaggregation of Revenue [Line Items]
Net sales	[1]	3,514	3,169	10,125	9,364
Industrial Packaging | EMEA
Disaggregation of Revenue [Line Items]
Net sales	[1]	383	394	1,371	1,213
Industrial Packaging | Pacific Rim and Asia
Disaggregation of Revenue [Line Items]
Net sales	[1]	12	15	44	43
Industrial Packaging | Americas, other than U.S.
Disaggregation of Revenue [Line Items]
Net sales	[1]	178	190	556	600
Global Cellulose Fibers
Disaggregation of Revenue [Line Items]
Net sales		729	564	1,981	1,737
Global Cellulose Fibers | Geography Eliminations [Member]
Disaggregation of Revenue [Line Items]
Net sales	[1]	729	564	1,981	1,737
Global Cellulose Fibers | Operating Segments [Member]
Disaggregation of Revenue [Line Items]
Net sales		729	564	1,981	1,737
Global Cellulose Fibers | Global Cellulose Fibers
Disaggregation of Revenue [Line Items]
Net sales		729	564	1,981	1,737
Global Cellulose Fibers | United States
Disaggregation of Revenue [Line Items]
Net sales	[1]	623	479	1,682	1,507
Global Cellulose Fibers | EMEA
Disaggregation of Revenue [Line Items]
Net sales	[1]	69	59	209	175
Global Cellulose Fibers | Pacific Rim and Asia
Disaggregation of Revenue [Line Items]
Net sales	[1]	37	26	90	55
Global Cellulose Fibers | Americas, other than U.S.
Disaggregation of Revenue [Line Items]
Net sales	[1]	0	0	0	0
Printing Papers
Disaggregation of Revenue [Line Items]
Net sales		846	743	2,473	2,234
Printing Papers | Geography Eliminations [Member]
Disaggregation of Revenue [Line Items]
Net sales	[1]	846	743	2,473	2,234
Printing Papers | Operating Segments [Member]
Disaggregation of Revenue [Line Items]
Net sales		846	743	2,473	2,234
Printing Papers | Intersegment Eliminations [Member]
Disaggregation of Revenue [Line Items]
Net sales		3	(1)	(8)	(1)
Printing Papers | North American Printing Papers
Disaggregation of Revenue [Line Items]
Net sales		425	362	1,201	1,073
Printing Papers | Brazilian Papers
Disaggregation of Revenue [Line Items]
Net sales		200	150	557	434
Printing Papers | European Papers
Disaggregation of Revenue [Line Items]
Net sales		218	232	723	728
Printing Papers | United States
Disaggregation of Revenue [Line Items]
Net sales	[1]	425	362	1,195	1,069
Printing Papers | EMEA
Disaggregation of Revenue [Line Items]
Net sales	[1]	232	244	765	765
Printing Papers | Pacific Rim and Asia
Disaggregation of Revenue [Line Items]
Net sales	[1]	8	6	25	20
Printing Papers | Americas, other than U.S.
Disaggregation of Revenue [Line Items]
Net sales	[1]	$ 181	$ 131	$ 488	$ 380

[1] Net sales are attributed to countries based on the location of the seller.