Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

+ Details

Name:	us-gaap_BusinessAcquisitionLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

The number of businesses acquired by the entity during the period.

+ References

No definition available.

+ Details

Name:	us-gaap_NumberOfBusinessesAcquired
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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3213-108585

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

Name:	us-gaap_BusinessAcquisitionAxis=ip_DSSmithPackagingMember
Namespace Prefix:
Data Type:	na
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- Details

Name:	us-gaap_BusinessAcquisitionAxis=ip_CorrugatedSheetPlantMember
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Acquisitions (Narrative) (Details) € in Millions	12 Months Ended
Acquisitions (Narrative) (Details) € in Millions	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2019 EUR (€)	Dec. 31, 2018 USD ($)	Apr. 30, 2020
Business Acquisition [Line Items]
Payments to acquire businesses, net of cash acquired	$ 65,000,000	$ 103,000,000		$ 8,000,000
DS Smith Packaging [Member]
Business Acquisition [Line Items]
Payments to acquire businesses, net of cash acquired		$ 81,000,000	€ 71
Number of Businesses Acquired		2	2
Corrugated Sheet Plant [Member]
Business Acquisition [Line Items]
Equity Method Investment, Ownership Percentage	40.00%				7.00%
Payments to acquire businesses, net of cash acquired	$ 56,000,000