Variable Interest Entities And Preferred Securities Of Subsidiaries (Narrative) (Details) a in Thousands, $ in Millions		1 Months Ended		3 Months Ended	12 Months Ended
		Aug. 31, 2021	Oct. 31, 2007 USD ($) a	Dec. 31, 2015 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2006 USD ($) a	Dec. 31, 2007 USD ($)
Variable Interest Entity [Line Items]
Long-term debt					$ 10,846	$ 11,075
Deferred tax liabilities, other					1,500
Payments to Acquire Investments					0	0	$ 198
Extinguishment of Debt, Amount	[1]				993	266	2,151
Financing Receivable, Gross					7,051	7,033
Cash, cash equivalents, and short-term investments					1,018	1,033
Letters of credit issued									$ 2,400
Notes receivable, fair value disclosure					2,300	2,200
Long-term debt									2,100
Long-term debt, fair value					$ 2,100	2,100
Variable Interest Entity, Not Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Forestlands average sales | a			1,550
Amount of consideration received			$ 2,400
ip_timber note maturity date			Oct. 31, 2027
Maturity date			Nov. 05, 2027
Variable Interest Entity, Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
International Paper debt obligations held by the Entities				$ 150			150
Long-term debt				$ 4,200			4,200
Timber Notes Maturity Extension				5 years
Payments to Acquire Investments							198
Letters of credit downgrade period of replacement					60 days
Financing Receivable, Gross				$ 4,800			4,800
ip_Extension Loans requiring LC banks to maintain credit rating at or above a specified threshold				1,100			$ 1,100
Maturity date							Dec. 31, 2020
Notes receivable, fair value disclosure					$ 4,800	4,700
Long-term debt, fair value					4,300	$ 4,300
Entities [Member]
Variable Interest Entity [Line Items]
Forestlands average sales | a								5,600
Amount of consideration received								$ 4,800
Deferred tax liabilities, other				1,400	884		$ 1,400
2015 Refinance Loans [Domain]
Variable Interest Entity [Line Items]
Long-term debt				$ 4,200			$ 4,200
Maturity date							May 25, 2016
Two Thousand Seven Monetized Notes [Member]
Variable Interest Entity [Line Items]
Deferred tax liabilities, other					$ 538				$ 831
Letters of credit downgrade period of replacement			30 days
Scenario, Forecast [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
ip_timber note maturity date		Aug. 25, 2021
Variable Interest Entity, Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Extinguishment of Debt, Amount							$ 630

[1] Reductions related to notes with interest rates ranging from 1.57% to 9.38% with original maturities from 2015 to 2030 for the years ended December 31, 2017, 2016 and 2015. Includes the $630 million payment for a portion of the Special Purpose Entity Liability for the year ended December 31, 2015 (see Note 12 Variable Interest Entities).