EQUITY Table (Details) - USD ($)	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019	Dec. 31, 2018
Beginning Balance	$ 7,718,000,000	$ 7,383,000,000
Stockholders' Equity Attributable to Parent	6,857,000,000		$ 7,713,000,000
Cumulative effect of new accounting principle in period of adoption	8,062,000,000		8,408,000,000
Issuance of stock for various plans, net	41,000,000	45,000,000
Repurchase of stock	(41,000,000)	(229,000,000)
Common stock dividends	(203,000,000)	(207,000,000)
Transactions of equity method investees	6,000,000	(3,000,000)
Comprehensive income (loss)	(658,000,000)	480,000,000
Stockholders' equity attributable to noncontrolling interest	4,000,000		5,000,000
Ending Balance	6,861,000,000	7,469,000,000
Common Stock Issued
Stockholders' Equity Attributable to Parent	449,000,000	449,000,000	449,000,000	$ 449,000,000
Paid-in Capital
Stockholders' Equity Attributable to Parent	6,252,000,000	6,159,000,000	6,297,000,000	6,280,000,000
Issuance of stock for various plans, net	(51,000,000)	(118,000,000)
Transactions of equity method investees	6,000,000	(3,000,000)
Retained Earnings
Stockholders' Equity Attributable to Parent	8,062,000,000	8,211,000,000	8,408,000,000	7,465,000,000
Common stock dividends	(203,000,000)	(207,000,000)
Comprehensive income (loss)	(141,000,000)	424,000,000
Accumulated Other Comprehensive Income (Loss)
Stockholders' Equity Attributable to Parent	(5,255,000,000)	(4,975,000,000)	(4,739,000,000)	(4,500,000,000)
Comprehensive income (loss)	(516,000,000)	54,000,000
Treasury Stock
Stockholders' Equity Attributable to Parent	2,651,000,000	2,398,000,000	2,702,000,000	2,332,000,000
Issuance of stock for various plans, net	(92,000,000)	(163,000,000)
Repurchase of stock	41,000,000	229,000,000
Total International Paper Shareholders’ Equity
Stockholders' Equity Attributable to Parent	6,857,000,000	7,446,000,000	7,713,000,000	7,362,000,000
Issuance of stock for various plans, net	41,000,000	45,000,000
Repurchase of stock	(41,000,000)	(229,000,000)
Common stock dividends	(203,000,000)	(207,000,000)
Transactions of equity method investees	6,000,000	(3,000,000)
Comprehensive income (loss)	(657,000,000)	478,000,000
Noncontrolling Interests
Comprehensive income (loss), portion attributable to noncontrolling interest	(1,000,000)	2,000,000
Stockholders' equity attributable to noncontrolling interest	4,000,000	23,000,000	$ 5,000,000	$ 21,000,000
Accounting Standards Update 2016-13 [Member]
Cumulative effect of new accounting principle in period of adoption	(2,000,000)
Accounting Standards Update 2016-13 [Member] | Retained Earnings
Cumulative effect of new accounting principle in period of adoption	(2,000,000)
Accounting Standards Update 2016-13 [Member] | Total International Paper Shareholders’ Equity
Cumulative effect of new accounting principle in period of adoption	$ (2,000,000)
Accounting Standards Update 2016-13 [Member]
Cumulative effect of new accounting principle in period of adoption		0
Accounting Standards Update 2016-13 [Member] | Retained Earnings
Cumulative effect of new accounting principle in period of adoption		529,000,000
Accounting Standards Update 2016-13 [Member] | Accumulated Other Comprehensive Income (Loss)
Cumulative effect of new accounting principle in period of adoption		(529,000,000)
Accounting Standards Update 2016-13 [Member] | Total International Paper Shareholders’ Equity
Cumulative effect of new accounting principle in period of adoption		$ 0