Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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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.

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INCENTIVE PLANS - Narrative (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
	Oct. 15, 2021	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation cost		$ 3	$ 4	$ 10	$ 11
International Paper
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation cost		$ 3	$ 3	$ 8	$ 9
Restricted Stock Units (RSUs) \| Share-based Payment Arrangement, Employee \| Subsequent Event
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted in period (in shares)	664,569
Vesting period	1 year 4 months 24 days