(Information By Industry Segment, Capital Spending) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Segment Reporting Information [Line Items]
Capital Spending	$ 1,276	$ 1,572	$ 1,280
Subtotal
Segment Reporting Information [Line Items]
Capital Spending	1,256	1,547	1,259
Subtotal | Industrial Packaging
Segment Reporting Information [Line Items]
Capital Spending	922	1,061	836
Subtotal | Global Cellulose Fibers
Segment Reporting Information [Line Items]
Capital Spending	162	183	188
Subtotal | Printing Papers
Segment Reporting Information [Line Items]
Capital Spending	172	303	235
Corporate and other
Segment Reporting Information [Line Items]
Capital Spending	$ 20	$ 25	$ 21