(Information By Industry Segment, External Sales By Major Product) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Segment Reporting Information [Line Items]
Net Sales	$ 20,580	$ 22,376	$ 23,306
Operating Segments [Member] | Industrial Packaging
Segment Reporting Information [Line Items]
Net Sales	14,983	15,259	15,828
Operating Segments [Member] | Global Cellulose Fibers
Segment Reporting Information [Line Items]
Net Sales	2,317	2,545	2,810
Operating Segments [Member] | Printing Papers
Segment Reporting Information [Line Items]
Net Sales	3,016	4,284	4,359
Corporate and other | Corporate and Other
Segment Reporting Information [Line Items]
Net Sales	$ 264	$ 288	$ 309