EQUITY Table (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Jun. 30, 2019	Dec. 31, 2018	Jun. 30, 2018	Dec. 31, 2017
Beginning Balance	$ 7,499,000,000	$ 6,864,000,000	$ 7,383,000,000	$ 6,541,000,000
Stockholders' Equity Attributable to Parent	7,441,000,000		7,441,000,000			$ 7,362,000,000
Adoption of ASC 606 revenue from contracts with customers		73,000,000		73,000,000
Issuance of stock for various plans, net	33,000,000	37,000,000	113,000,000	112,000,000
Repurchase of stock	(75,000,000)	(201,000,000)	(535,000,000)	(532,000,000)
Common stock dividends	(199,000,000)	(197,000,000)	(607,000,000)	(596,000,000)
Transactions of equity method investees	0	1,000,000	33,000,000	19,000,000
Comprehensive income (loss)	198,000,000	554,000,000	1,069,000,000	1,441,000,000
Stockholders' equity attributable to noncontrolling interest	15,000,000		15,000,000			21,000,000
Ending Balance	7,456,000,000	7,058,000,000	7,456,000,000	7,058,000,000
Common Stock Issued
Stockholders' Equity Attributable to Parent	449,000,000	449,000,000	449,000,000	449,000,000	$ 449,000,000	449,000,000	$ 449,000,000	$ 449,000,000
Paid-in Capital
Stockholders' Equity Attributable to Parent	6,261,000,000	6,256,000,000	6,261,000,000	6,256,000,000	6,229,000,000	6,280,000,000	6,219,000,000	6,206,000,000
Issuance of stock for various plans, net	32,000,000	36,000,000	(52,000,000)	31,000,000
Transactions of equity method investees	0	1,000,000	33,000,000	19,000,000
Retained Earnings
Stockholders' Equity Attributable to Parent	8,447,000,000	7,353,000,000	8,447,000,000	7,353,000,000	8,302,000,000	7,465,000,000	6,988,000,000	6,180,000,000
Adoption of ASU 2018-02 reclassification of stranded tax effects resulting from Tax Reform			529,000,000
Adoption of ASC 606 revenue from contracts with customers		73,000,000		73,000,000
Common stock dividends	(199,000,000)	(197,000,000)	(607,000,000)	(596,000,000)
Comprehensive income (loss)	344,000,000	562,000,000	1,060,000,000	1,696,000,000
Accumulated Other Comprehensive Income (Loss)
Stockholders' Equity Attributable to Parent	(5,014,000,000)	(4,887,000,000)	(5,014,000,000)	(4,887,000,000)	(4,870,000,000)	(4,500,000,000)	(4,881,000,000)	(4,633,000,000)
Adoption of ASU 2018-02 reclassification of stranded tax effects resulting from Tax Reform			(529,000,000)
Comprehensive income (loss)	(144,000,000)	(6,000,000)	15,000,000	(254,000,000)
Treasury Stock
Stockholders' Equity Attributable to Parent	2,702,000,000	2,131,000,000	2,702,000,000	2,131,000,000	2,628,000,000	2,332,000,000	1,931,000,000	1,680,000,000
Issuance of stock for various plans, net	(1,000,000)	(1,000,000)	(165,000,000)	(81,000,000)
Repurchase of stock	75,000,000	201,000,000	535,000,000	532,000,000
Total International Paper Shareholders’ Equity
Stockholders' Equity Attributable to Parent	7,441,000,000	7,040,000,000	7,441,000,000	7,040,000,000	7,482,000,000	7,362,000,000	6,844,000,000	6,522,000,000
Adoption of ASC 606 revenue from contracts with customers		73,000,000		73,000,000
Issuance of stock for various plans, net	33,000,000	37,000,000	113,000,000	112,000,000
Repurchase of stock	(75,000,000)	(201,000,000)	(535,000,000)	(532,000,000)
Common stock dividends	(199,000,000)	(197,000,000)	(607,000,000)	(596,000,000)
Transactions of equity method investees	0	1,000,000	33,000,000	19,000,000
Comprehensive income (loss)	200,000,000	556,000,000	1,075,000,000	1,442,000,000
Noncontrolling Interests
Comprehensive income (loss), portion attributable to noncontrolling interest	(2,000,000)	(2,000,000)	(6,000,000)	(1,000,000)
Stockholders' equity attributable to noncontrolling interest	$ 15,000,000	$ 18,000,000	$ 15,000,000	$ 18,000,000	$ 17,000,000	$ 21,000,000	$ 20,000,000	$ 19,000,000