Equity Method Investments Narrative (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Schedule of Equity Method Investments [Line Items]
Equity earnings (loss), net of taxes	$ 336	$ 177	$ 198
Reportable Subsegments [Member] \| Graphic Packaging LLC [Member]
Schedule of Equity Method Investments [Line Items]
Percentage of equity interest	20.50%
Equity earnings (loss), net of taxes	$ 46
Dividends received from equity method investee	25
Equity method investments	1,100
Equity method investment, difference between carrying amount and underlying equity	562
Revenue from related party	$ 240
Reportable Subsegments [Member] \| Ilim Holding [Member]
Schedule of Equity Method Investments [Line Items]
Percentage of equity interest	50.00%
Equity earnings (loss), net of taxes	$ 290	183	199
Foreign currency transaction gain (loss), net of tax	(82)	15	25
Dividends received from equity method investee	128	133
Equity method investments	478	338
Equity method investment, difference between carrying amount and underlying equity	145	154
Purchases from related party	$ 214	$ 205	$ 170

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This element represents disclosure of the aggregate cash dividends paid to the entity by 50% or less owned persons accounted for using the equity method.

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Difference between amount at which an investment accounted for under the equity method of accounting is carried (reported) on the balance sheet and amount of underlying equity in net assets the reporting Entity has in the investee.

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

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

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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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