Segment Information - Schedule of Segment Information (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Segment Reporting Information [Line Items]
Revenue from contract with customer	$ 1,594.6	$ 1,501.6
Revenues	1,599.1	1,505.9
Income (Loss) from Operations	160.1	134.2
Depreciation and Amortization	113.6	117.1
Operating Segments \| Paperboard Mills
Segment Reporting Information [Line Items]
Revenue from contract with customer	268.5	275.5
Income (Loss) from Operations	(22.9)	(4.0)
Depreciation and Amortization	59.0	56.2
Operating Segments \| Americas Paperboard Packaging
Segment Reporting Information [Line Items]
Revenue from contract with customer	1,123.4	1,022.8
Income (Loss) from Operations	194.8	125.6
Depreciation and Amortization	39.4	43.7
Operating Segments \| Europe Paperboard Packaging
Segment Reporting Information [Line Items]
Revenue from contract with customer	176.8	173.8
Income (Loss) from Operations	12.0	19.2
Depreciation and Amortization	9.8	11.8
Corporate/Other/Eliminations
Segment Reporting Information [Line Items]
Revenues	30.4	33.8
Income (Loss) from Operations	(23.8)	(6.6)
Depreciation and Amortization	$ 5.4	$ 5.4

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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