(Reconciliation Of Earnings Per Share) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Earnings (loss) from continuing operations attributable to International Paper common shareholders									$ 1,122	$ 230	$ 699
Weighted average common shares outstanding									389.4	393.0	395.3
Effect of dilutive securities:									3.0	2.7	3.5
Weighted average common shares outstanding  – assuming dilution									392.4	395.7	398.8
Basic earnings (loss) per share from continuing operations	$ 0.30	$ 1.11	$ 0.79	$ 0.68	$ 0.17	$ 0.38	$ 0.64	$ (0.59)	$ 2.88	$ 0.59	$ 1.77
Diluted earnings (loss) per share from continuing operations	$ 0.30	$ 1.10	$ 0.78	$ 0.68	$ 0.17	$ 0.38	$ 0.64	$ (0.59)	$ 2.86	$ 0.58	$ 1.75