Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
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-Section S99
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Name:	us-gaap_RestructuringCharges
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Segment Information - Selected Financial Information by Reportable Segment (Parenthetical) (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
	May 31, 2020	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2020
Segment Reporting Information [Line Items]
Goodwill impairment charge		$ 55.2		$ 55.2
Paper Reporting Unit
Segment Reporting Information [Line Items]
Goodwill impairment charge	$ 55.2
Wallula, Washington Mill
Segment Reporting Information [Line Items]
Restructuring charges				0.6
Packaging and Paper
Segment Reporting Information [Line Items]
Restructuring charges			$ 20.4	20.8
Packaging and Paper \| COVID-19
Segment Reporting Information [Line Items]
Incremental out-of-pocket costs			$ 6.1	$ 6.9