EQUITY Table (Details) - USD ($)	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Balance, January 1	$ 7,383,000,000	$ 6,541,000,000
Adoption of ASU 2018-02 reclassification of stranded tax effects resulting from Tax Reform	0	73,000,000
Issuance of stock for various plans, net	45,000,000	38,000,000
Repurchase of stock	(229,000,000)	(31,000,000)
Common stock dividends ($.5000 per share)	(207,000,000)	(199,000,000)
Transactions of equity method investees	(3,000,000)	10,000,000
Comprehensive income (loss)	480,000,000	833,000,000
Ending Balance, March 31	7,469,000,000	7,265,000,000
Common Stock Issued
Balance, January 1	449,000,000	449,000,000
Adoption of ASU 2018-02 reclassification of stranded tax effects resulting from Tax Reform	0	0
Issuance of stock for various plans, net	0	0
Repurchase of stock	0	0
Common stock dividends ($.5000 per share)	0	0
Transactions of equity method investees	0	0
Comprehensive income (loss)	0	0
Ending Balance, March 31	449,000,000	449,000,000
Paid-in Capital
Balance, January 1	6,280,000,000	6,206,000,000
Adoption of ASU 2018-02 reclassification of stranded tax effects resulting from Tax Reform	0	0
Issuance of stock for various plans, net	(118,000,000)	(41,000,000)
Repurchase of stock	0	0
Common stock dividends ($.5000 per share)	0	0
Transactions of equity method investees	(3,000,000)	10,000,000
Comprehensive income (loss)	0	0
Ending Balance, March 31	6,159,000,000	6,175,000,000
Retained Earnings
Balance, January 1	7,465,000,000	6,180,000,000
Adoption of ASU 2018-02 reclassification of stranded tax effects resulting from Tax Reform	529,000,000	73,000,000
Issuance of stock for various plans, net	0	0
Repurchase of stock	0	0
Common stock dividends ($.5000 per share)	(207,000,000)	(199,000,000)
Transactions of equity method investees	0	0
Comprehensive income (loss)	424,000,000	729,000,000
Ending Balance, March 31	8,211,000,000	6,783,000,000
Accumulated Other Comprehensive Income (Loss)
Balance, January 1	(4,500,000,000)	(4,633,000,000)
Adoption of ASU 2018-02 reclassification of stranded tax effects resulting from Tax Reform	(529,000,000)	0
Issuance of stock for various plans, net	0	0
Repurchase of stock	0	0
Common stock dividends ($.5000 per share)	0	0
Transactions of equity method investees	0	0
Comprehensive income (loss)	54,000,000	103,000,000
Ending Balance, March 31	(4,975,000,000)	(4,530,000,000)
Treasury Stock
Balance, January 1	2,332,000,000	1,680,000,000
Adoption of ASU 2018-02 reclassification of stranded tax effects resulting from Tax Reform	0	0
Issuance of stock for various plans, net	(163,000,000)	(79,000,000)
Repurchase of stock	229,000,000	31,000,000
Common stock dividends ($.5000 per share)	0	0
Transactions of equity method investees	0	0
Comprehensive income (loss)	0	0
Ending Balance, March 31	2,398,000,000	1,632,000,000
Total International Paper Shareholders’ Equity
Balance, January 1	7,362,000,000	6,522,000,000
Adoption of ASU 2018-02 reclassification of stranded tax effects resulting from Tax Reform	0	73,000,000
Issuance of stock for various plans, net	45,000,000	38,000,000
Repurchase of stock	(229,000,000)	(31,000,000)
Common stock dividends ($.5000 per share)	(207,000,000)	(199,000,000)
Transactions of equity method investees	(3,000,000)	10,000,000
Comprehensive income (loss)	478,000,000	832,000,000
Ending Balance, March 31	7,446,000,000	7,245,000,000
Noncontrolling Interests
Balance, January 1	21,000,000	19,000,000
Adoption of ASU 2018-02 reclassification of stranded tax effects resulting from Tax Reform	0	0
Issuance of stock for various plans, net	0	0
Repurchase of stock	0	0
Transactions of equity method investees	0	0
Comprehensive income (loss)	2,000,000	1,000,000
Ending Balance, March 31	$ 23,000,000	$ 20,000,000