COMMITMENTS AND CONTINGENCIES (Note)	9 Months Ended
Sep. 30, 2020
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies [Note Text Block]	Environmental International Paper has been named as a potentially responsible party (PRP) in environmental remediation actions under various federal and state laws, including the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA). Many of these proceedings involve the cleanup of hazardous substances at large commercial landfills that received waste from many different sources. While joint and several liability is authorized under CERCLA and equivalent state laws, as a practical matter, liability for CERCLA cleanups is typically allocated among the many PRPs. There are other remediation costs typically associated with the cleanup of hazardous substances at the Company’s current, closed or formerly-owned facilities, and recorded as liabilities in the balance sheet. Remediation costs are recorded in the consolidated financial statements when they become probable and reasonably estimable. International Paper has estimated the probable liability associated with these environmental remediation matters, including those described herein, to be approximately $186 million ($195 million undiscounted) in the aggregate as of September 30, 2020. Other than as described below, completion of required remedial actions is not expected to have a material effect on our consolidated financial statements. Cass Lake: One of the matters included above arises out of a closed wood-treatment facility located in Cass Lake, Minnesota. In June 2011, the United States Environmental Protection Agency (EPA) selected and published a proposed soil remedy at the site with an estimated cost of $45 million at September 30, 2020. In April 2020, the EPA issued a final plan concerning clean-up standards at a portion of the site, the estimated cost of which is included within the reserve referenced above. In October 2012, the Natural Resource Trustees for this site provided notice to International Paper and other PRPs of their intent to perform a Natural Resource Damage Assessment. It is premature to predict the outcome of the assessment or to estimate a loss or range of loss, if any, in excess of the applicable reserve referenced above, which may be incurred. Kalamazoo River: The Company is a PRP with respect to the Allied Paper, Inc./Portage Creek/Kalamazoo River Superfund Site in Michigan. The EPA asserts that the site is contaminated by polychlorinated biphenyls (PCBs) primarily as a result of discharges from various paper mills located along the Kalamazoo River, including a paper mill (the Allied Paper Mill) formerly owned by St. Regis Paper Company (St. Regis). The Company is a successor in interest to St. Regis. •Operable Unit 5, Area 1: In March 2016, the Company and other PRPs received a special notice letter from the EPA (i) inviting participation in implementing a remedy for a portion of the site known as Operable Unit 5, Area 1, and (ii) demanding reimbursement of EPA past costs totaling $37 million, including $19 million in past costs previously demanded by the EPA. The Company responded to the special notice letter. In December 2016, the EPA issued a unilateral administrative order to the Company and other PRPs to perform the remedy. The Company responded to the unilateral administrative order, agreeing to comply with the order subject to its sufficient cause defenses. •Operable Unit 5, Area 2: In September 2017, the EPA issued a Record of Decision selecting the final remedy for a portion of the site known as Operable Unit 5, Area 2, but has not yet issued a special notice letter for implementing the remedy. •Operable Unit 1: In October 2016, the Company and another PRP received a special notice letter from the EPA inviting participation in the remedial design component of the landfill remedy for the Allied Paper Mill, which is also known as Operable Unit 1. The Record of Decision establishing the final landfill remedy for the Allied Paper Mill was issued by the EPA in September 2016. The Company responded to the Allied Paper Mill special notice letter in December 2016. In February 2017, the EPA informed the Company that it would make other arrangements for the performance of the remedial design. In addition, in December 2019, the United States published notice in the Federal Register of a proposed consent decree with NCR Corporation (one of the parties to the allocation/apportionment litigation described below), the State of Michigan and natural resource trustees under which NCR would make payments of more than $100 million and perform work at the Site at an estimated cost of $135.7 million. The public comment period with respect to the proposed consent decree closed in February 2020 and we are awaiting the court's final decision. The Company’s CERCLA liability has not been finally determined with respect to these or any other portions of the site, and except as noted above, the Company has declined to perform any work or reimburse the EPA at this time. As noted below, the Company is involved in allocation/apportionment litigation with regard to the site. Accordingly, it is premature to predict the outcome or estimate our maximum reasonably possible loss or range of loss with respect to this site. We have recorded a liability for future remediation costs at the site that are probable and reasonably estimable, and it remains reasonably possible that additional losses in excess of this recorded liability could be material. The Company was named as a defendant by Georgia-Pacific Consumer Products LP, Fort James Corporation and Georgia Pacific LLC in a contribution and cost recovery action for alleged pollution at the site. NCR Corporation and Weyerhaeuser Company are also named as defendants in the suit. The suit seeks contribution under CERCLA for costs purportedly expended by plaintiffs ($79 million as of the filing of the complaint) and for future remediation costs. In June 2018, the Court issued its Final Judgment and Order, which fixed the past cost amount at approximately $50 million (plus interest to be determined) and allocated to the Company a 15% share of responsibility for those past costs. The Court did not address responsibility for future costs in its decision. In July 2018, the Company and each of the other parties filed notices appealing the Final Judgment and prior orders incorporated into that Judgment. The proposed consent decree by NCR described above, if entered, would result in the termination of NCR's involvement in the appeal. Harris County: International Paper and McGinnis Industrial Maintenance Corporation (MIMC), a subsidiary of Waste Management, Inc. (WMI), are PRPs at the San Jacinto River Waste Pits Superfund Site in Harris County, Texas. The PRPs have been actively participating in the activities at the site and share the costs of these activities. In October 2017, the EPA issued a Record of Decision (ROD) selecting the final remedy for the site: removal and relocation of the waste material from both the northern and southern impoundments. The EPA did not specify the methods or practices needed to perform this work. The EPA’s selected remedy was accompanied by a cost estimate of approximately $115 million ($105 million for the northern impoundment, and $10 million for the southern impoundment). Subsequent to the issuance of the ROD, there have been numerous meetings between the EPA and the PRPs, and the Company continues to work with the EPA and MIMC/WMI to develop the remedial design. To this end, in April 2018, the PRPs entered into an Administrative Order on Consent (AOC) with the EPA, agreeing to work together to develop the remedial design until April 2021. The AOC does not include any agreement to perform waste removal or other construction activity at the site. Rather, it involves adaptive management techniques and a pre-design investigation, the objectives of which include filling data gaps (including but not limited to post-Hurricane Harvey technical data generated prior to the ROD and not incorporated into the selected remedy), refining areas and volumes of materials to be addressed, determining if an excavation remedy is able to be implemented in a manner protective of human health and the environment, and investigating potential impacts of remediation activities to infrastructure in the vicinity. During the first quarter of 2020, through a series of meetings among the Company, MIMC/WMI, our consultants, the EPA and the Texas Commission on Environmental Quality (TCEQ), progress was made to resolve key technical issues previously preventing the Company from determining the manner in which the selected remedy for the northern impoundment would be feasibly implemented. As a result of these developments, as of September 30, 2020, the Company has reserved the following amounts in relation to remediation at this site: (a) $10 million for the southern impoundment; and (b) $55 million for the northern impoundment, which represents the Company's 50% share of our estimate of the low end of the range of probable remediation costs. Although key technical issues have been resolved, we still face significant challenges remediating the northern impoundment in a cost-efficient manner and without a release to the environment and therefore our discussions with the EPA on the best approach to remediation will continue. Because of ongoing questions regarding cost effectiveness, timing and gathering other technical data, additional losses in excess of our recorded liability are possible. We are currently unable to reasonably estimate any further adjustment to our recorded liability or any loss or range of loss in excess of such liability; however, we believe it is unlikely any adjustment would be material. Asbestos-Related Matters We have been named as a defendant in various asbestos-related personal injury litigation, in both state and federal court, primarily in relation to the prior operations of certain companies previously acquired by the Company. The Company regularly conducts a comprehensive legal review of its asbestos liabilities and reviews recent and historical claims data. During the second quarter of 2020, as previously disclosed, we adjusted our estimated net liability associated with asbestos-related litigation concerning products sold by Champion International Corporation prior to our acquisition of Champion in 2000 to revise the time period associated with anticipated future claims through 2059, a commonly viewed end point when such claims are more predictable. We concluded the adjustment of $43 million to increase this net liability, which resulted in a liability of $75 million, net of estimated insurance recoveries, was not material to any period. As of September 30, 2020, the Company's total recorded liability with respect to pending and future asbestos-related claims was $117 million, net of estimated insurance recoveries. While it is reasonably possible that the Company may incur losses in excess of its recorded liability with respect to asbestos-related matters, we do not believe additional material losses are probable. Antitrust Italy: In March 2017, the Italian Competition Authority (ICA) commenced an investigation into the Italian packaging industry to determine whether producers of corrugated sheets and boxes violated the applicable European competition law. In April 2019, the ICA concluded its investigation and issued initial findings alleging that over 30 producers, including our Italian packaging subsidiary (IP Italy), improperly coordinated the production and sale of corrugated sheets and boxes. On August 6, 2019, the ICA issued its decision and assessed IP Italy a fine of €29 million (approximately $32 million at current exchange rates) which was recorded in the third quarter of 2019. However, we are vigorously appealing this decision of the ICA to the Italian courts and have numerous and strong bases for our appeal. Contract Signature: In August 2014, a lawsuit captioned Signature Industrial Services LLC et al. v. International Paper Company was filed in state court in Texas. The Signature lawsuit arises out of approximately $1 million in disputed invoices related to the installation of new equipment at the Company's Orange, Texas mill. In addition to the invoices in dispute, Signature and its president allege consequential damages arising from the Company's nonpayment of those invoices. The lawsuit was tried before a jury in Beaumont, Texas, in May 2017. On June 1, 2017, the jury returned a verdict awarding approximately $125 million in damages to the plaintiffs. The Court issued a judgment on December 14, 2017, awarding the plaintiffs a total of approximately $137 million in actual and consequential damages, fees, costs and pre-judgment interest, and awarding post-judgment interest. The Company appealed this judgment and, on April 30, 2020, the Court of Appeals for the Thirteenth District of Texas issued a decision affirming in part and reversing and rendering judgment in favor of the Company in part. The Court affirmed approximately $14.8 million of the judgment. Otherwise, the Court rendered judgment in favor of the Company on the remainder of the jury’s verdict. The Company continues to have strong bases by which to challenge the affirmed portions of the award and has presented those arguments on appeal to the Supreme Court of Texas. The plaintiffs have also appealed the decision of the appellate court. We do not expect that potential losses, if any, related to this lawsuit will be material. Taxes Other Than Payroll Taxes In 2017, the Brazilian Federal Supreme Court decided that the state value-added tax (VAT) should not be included in the basis of federal VAT calculations. In 2018 and 2019, the Brazilian tax authorities published both an internal consultation and a normative ruling with a narrow interpretation of the effects of the case. We have determined that any related federal VAT refunds should be recognized when they are both probable and reasonably estimable. Based upon the best information available to us, we have determined that the amount of refund that is probable of being realized is limited to that determined by the tax authorities' narrow interpretation, for which we have recognized a receivable of $11 million as of September 30, 2020. It is possible that future court decisions and guidance from the tax authorities could expand the scope of the federal VAT refunds. General The Company is involved in various other inquiries, administrative proceedings and litigation relating to environmental and safety matters, personal injury, product liability, labor and employment, contracts, sales of property, intellectual property, tax, and other matters, some of which allege substantial monetary damages. See Note 14 for details regarding a tax matter. Assessments of lawsuits and claims can involve a series of complex judgments about future events, can rely heavily on estimates and assumptions, and are otherwise subject to significant uncertainties. As a result, there can be no certainty that the Company will not ultimately incur charges in excess of presently recorded liabilities. The Company believes that loss contingencies arising from pending matters including the matters described herein, will not have a material effect on the consolidated financial position or liquidity of the Company. However, in light of the inherent uncertainties involved in pending or threatened legal matters, some of which are beyond the Company's control, and the large or indeterminate damages sought in some of these matters, a future adverse ruling, settlement, unfavorable development, or increase in accruals with respect to these matters could result in future charges that could be material to the Company's results of operations or cash flows in any particular reporting period.

International Paper has been named as a potentially responsible party (PRP) in environmental remediation actions under various federal and state laws, including the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA). Many of these proceedings involve the cleanup of hazardous substances at large commercial landfills that received waste from many different sources. While joint and several liability is authorized under CERCLA and equivalent state laws, as a practical matter, liability for CERCLA cleanups is typically allocated among the many PRPs. There are other remediation costs typically associated with the cleanup of hazardous substances at the Company’s current, closed or formerly-owned facilities, and recorded as liabilities in the balance sheet.

Remediation costs are recorded in the consolidated financial statements when they become probable and reasonably estimable. International Paper has estimated the probable liability associated with these environmental remediation matters, including those described herein, to be approximately $186 million ($195 million undiscounted) in the aggregate as of September 30, 2020. Other than as described below, completion of required remedial actions is not expected to have a material effect on our consolidated financial statements.

Cass Lake: One of the matters included above arises out of a closed wood-treatment facility located in Cass Lake, Minnesota. In June 2011, the United States Environmental Protection Agency (EPA) selected and published a proposed soil remedy at the site with an estimated cost of $45 million at September 30, 2020. In April 2020, the EPA issued a final plan concerning clean-up standards at a portion of the site, the estimated cost of which is included within the reserve referenced above. In October 2012, the Natural Resource Trustees for this site provided notice to International Paper and other PRPs of their intent to perform a Natural Resource Damage Assessment. It is premature to predict the outcome of the assessment or to estimate a loss or range of loss, if any, in excess of the applicable reserve referenced above, which may be incurred.

Kalamazoo River: The Company is a PRP with respect to the Allied Paper, Inc./Portage Creek/Kalamazoo River Superfund Site in Michigan. The EPA asserts that the site is contaminated by polychlorinated biphenyls (PCBs) primarily as a result of discharges from various paper mills located along the Kalamazoo River, including a paper mill (the Allied Paper Mill) formerly owned by St. Regis Paper Company (St. Regis). The Company is a successor in interest to St. Regis.

•Operable Unit 5, Area 1: In March 2016, the Company and other PRPs received a special notice letter from the EPA (i) inviting participation in implementing a remedy for a portion of the site known as Operable Unit 5, Area 1, and (ii) demanding reimbursement of EPA past costs totaling $37 million, including $19 million in past costs previously demanded by the EPA. The Company responded to the special notice letter. In December 2016, the EPA issued a unilateral administrative order to the Company and other PRPs to perform the remedy. The Company responded to the unilateral administrative order, agreeing to comply with the order subject to its sufficient cause defenses.

•Operable Unit 1: In October 2016, the Company and another PRP received a special notice letter from the EPA inviting participation in the remedial design component of the landfill remedy for the Allied Paper Mill, which is also known as Operable Unit 1. The Record of Decision establishing the final landfill remedy for the Allied Paper Mill was

In addition, in December 2019, the United States published notice in the Federal Register of a proposed consent decree with NCR Corporation (one of the parties to the allocation/apportionment litigation described below), the State of Michigan and natural resource trustees under which NCR would make payments of more than $100 million and perform work at the Site at an estimated cost of $135.7 million. The public comment period with respect to the proposed consent decree closed in February 2020 and we are awaiting the court's final decision.

The Company’s CERCLA liability has not been finally determined with respect to these or any other portions of the site, and except as noted above, the Company has declined to perform any work or reimburse the EPA at this time. As noted below, the Company is involved in allocation/apportionment litigation with regard to the site. Accordingly, it is premature to predict the outcome or estimate our maximum reasonably possible loss or range of loss with respect to this site. We have recorded a liability for future remediation costs at the site that are probable and reasonably estimable, and it remains reasonably possible that additional losses in excess of this recorded liability could be material.

The Company was named as a defendant by Georgia-Pacific Consumer Products LP, Fort James Corporation and Georgia Pacific LLC in a contribution and cost recovery action for alleged pollution at the site. NCR Corporation and Weyerhaeuser Company are also named as defendants in the suit. The suit seeks contribution under CERCLA for costs purportedly expended by plaintiffs ($79 million as of the filing of the complaint) and for future remediation costs. In June 2018, the Court issued its Final Judgment and Order, which fixed the past cost amount at approximately $50 million (plus interest to be determined) and allocated to the Company a 15% share of responsibility for those past costs. The Court did not address responsibility for future costs in its decision. In July 2018, the Company and each of the other parties filed notices appealing the Final Judgment and prior orders incorporated into that Judgment. The proposed consent decree by NCR described above, if entered, would result in the termination of NCR's involvement in the appeal.

Harris County: International Paper and McGinnis Industrial Maintenance Corporation (MIMC), a subsidiary of Waste Management, Inc. (WMI), are PRPs at the San Jacinto River Waste Pits Superfund Site in Harris County, Texas. The PRPs have been actively participating in the activities at the site and share the costs of these activities.

In October 2017, the EPA issued a Record of Decision (ROD) selecting the final remedy for the site: removal and relocation of the waste material from both the northern and southern impoundments. The EPA did not specify the methods or practices needed to perform this work. The EPA’s selected remedy was accompanied by a cost estimate of approximately $115 million ($105 million for the northern impoundment, and $10 million for the southern impoundment). Subsequent to the issuance of the ROD, there have been numerous meetings between the EPA and the PRPs, and the Company continues to work with the EPA and MIMC/WMI to develop the remedial design.

To this end, in April 2018, the PRPs entered into an Administrative Order on Consent (AOC) with the EPA, agreeing to work together to develop the remedial design until April 2021. The AOC does not include any agreement to perform waste removal or other construction activity at the site. Rather, it involves adaptive management techniques and a pre-design investigation, the objectives of which include filling data gaps (including but not limited to post-Hurricane Harvey technical data generated prior to the ROD and not incorporated into the selected remedy), refining areas and volumes of materials to be addressed, determining if an excavation remedy is able to be implemented in a manner protective of human health and the environment, and investigating potential impacts of remediation activities to infrastructure in the vicinity.

During the first quarter of 2020, through a series of meetings among the Company, MIMC/WMI, our consultants, the EPA and the Texas Commission on Environmental Quality (TCEQ), progress was made to resolve key technical issues previously preventing the Company from determining the manner in which the selected remedy for the northern impoundment would be feasibly implemented. As a result of these developments, as of September 30, 2020, the Company has reserved the following amounts in relation to remediation at this site: (a) $10 million for the southern impoundment; and (b) $55 million for the northern impoundment, which represents the Company's 50% share of our estimate of the low end of the range of probable remediation costs.

Although key technical issues have been resolved, we still face significant challenges remediating the northern impoundment in a cost-efficient manner and without a release to the environment and therefore our discussions with the EPA on the best approach to remediation will continue. Because of ongoing questions regarding cost effectiveness, timing and gathering other technical data, additional losses in excess of our recorded liability are possible. We are currently unable to reasonably estimate

We have been named as a defendant in various asbestos-related personal injury litigation, in both state and federal court, primarily in relation to the prior operations of certain companies previously acquired by the Company. The Company regularly conducts a comprehensive legal review of its asbestos liabilities and reviews recent and historical claims data. During the second quarter of 2020, as previously disclosed, we adjusted our estimated net liability associated with asbestos-related litigation concerning products sold by Champion International Corporation prior to our acquisition of Champion in 2000 to revise the time period associated with anticipated future claims through 2059, a commonly viewed end point when such claims are more predictable. We concluded the adjustment of $43 million to increase this net liability, which resulted in a liability of $75 million, net of estimated insurance recoveries, was not material to any period. As of September 30, 2020, the Company's total recorded liability with respect to pending and future asbestos-related claims was $117 million, net of estimated insurance recoveries. While it is reasonably possible that the Company may incur losses in excess of its recorded liability with respect to asbestos-related matters, we do not believe additional material losses are probable.

Italy: In March 2017, the Italian Competition Authority (ICA) commenced an investigation into the Italian packaging industry to determine whether producers of corrugated sheets and boxes violated the applicable European competition law. In April 2019, the ICA concluded its investigation and issued initial findings alleging that over 30 producers, including our Italian packaging subsidiary (IP Italy), improperly coordinated the production and sale of corrugated sheets and boxes. On August 6, 2019, the ICA issued its decision and assessed IP Italy a fine of €29 million (approximately $32 million at current exchange rates) which was recorded in the third quarter of 2019. However, we are vigorously appealing this decision of the ICA to the Italian courts and have numerous and strong bases for our appeal.

Signature: In August 2014, a lawsuit captioned Signature Industrial Services LLC et al. v. International Paper Company was filed in state court in Texas. The Signature lawsuit arises out of approximately $1 million in disputed invoices related to the installation of new equipment at the Company's Orange, Texas mill. In addition to the invoices in dispute, Signature and its president allege consequential damages arising from the Company's nonpayment of those invoices. The lawsuit was tried before a jury in Beaumont, Texas, in May 2017. On June 1, 2017, the jury returned a verdict awarding approximately $125 million in damages to the plaintiffs. The Court issued a judgment on December 14, 2017, awarding the plaintiffs a total of approximately $137 million in actual and consequential damages, fees, costs and pre-judgment interest, and awarding post-judgment interest. The Company appealed this judgment and, on April 30, 2020, the Court of Appeals for the Thirteenth District of Texas issued a decision affirming in part and reversing and rendering judgment in favor of the Company in part. The Court affirmed approximately $14.8 million of the judgment. Otherwise, the Court rendered judgment in favor of the Company on the remainder of the jury’s verdict. The Company continues to have strong bases by which to challenge the affirmed portions of the award and has presented those arguments on appeal to the Supreme Court of Texas. The plaintiffs have also appealed the decision of the appellate court. We do not expect that potential losses, if any, related to this lawsuit will be material.

In 2017, the Brazilian Federal Supreme Court decided that the state value-added tax (VAT) should not be included in the basis of federal VAT calculations. In 2018 and 2019, the Brazilian tax authorities published both an internal consultation and a normative ruling with a narrow interpretation of the effects of the case. We have determined that any related federal VAT refunds should be recognized when they are both probable and reasonably estimable. Based upon the best information available to us, we have determined that the amount of refund that is probable of being realized is limited to that determined by the tax authorities' narrow interpretation, for which we have recognized a receivable of $11 million as of September 30, 2020. It is possible that future court decisions and guidance from the tax authorities could expand the scope of the federal VAT refunds.

The Company is involved in various other inquiries, administrative proceedings and litigation relating to environmental and safety matters, personal injury, product liability, labor and employment, contracts, sales of property, intellectual property, tax, and other matters, some of which allege substantial monetary damages. See Note 14 for details regarding a tax matter. Assessments of lawsuits and claims can involve a series of complex judgments about future events, can rely heavily on