Recoverability test results recoverable percentage.

No definition available.

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- Definition

Value of input used to measure alternative investment.

+ References

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- Definition

Indicates measurement input for alternative investment.

+ References

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- Definition

Indicates valuation technique for measuring alternative investment.

+ References

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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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- Definition

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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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.

+ References

No definition available.

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Goodwill and Intangible Assets -Goodwill - Additional Information (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
	May 31, 2020	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Goodwill [Line Items]
Goodwill impairment charge		$ 0.0	$ 55.2	$ 0.0	$ 55.2
Discount rate utilized	0.09
Alternative Investment, Valuation Technique [Extensible List]	us-gaap:IncomeApproachValuationTechniqueMember
Alternative Investment, Measurement Input [Extensible List]	us-gaap:MeasurementInputDiscountRateMember
Goodwill		863.5		863.5		$ 863.5
Packaging
Goodwill [Line Items]
Goodwill		$ 863.5		$ 863.5		$ 863.5
Paper
Goodwill [Line Items]
Recoverability test results recoverable percentage	100.00%
Paper Reporting Unit
Goodwill [Line Items]
Goodwill impairment charge	$ 55.2		$ 55.2		$ 55.2