Segment Information - Schedule of Segment Information (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Segment Reporting Information [Line Items]
Net Sales	$ 1,137.6	$ 1,103.7	$ 3,293.8	$ 3,240.9
Income (Loss) from Operations	95.4	105.1	258.5	317.9
Depreciation and Amortization	87.0	78.2	237.2	224.1
Corporate/Other/Eliminations
Segment Reporting Information [Line Items]
Net Sales	46.7	44.5	124.0	94.8
Income (Loss) from Operations	(2.7)	0.0	(12.9)	(19.5)
Depreciation and Amortization	5.5	3.7	14.3	8.6
Paperboard Mills | Operating Segments
Segment Reporting Information [Line Items]
Net Sales	105.1	95.6	300.1	293.9
Income (Loss) from Operations	(13.4)	(2.5)	(36.0)	(2.0)
Depreciation and Amortization	39.5	29.6	101.3	90.3
Americas Paperboard Packaging | Operating Segments
Segment Reporting Information [Line Items]
Net Sales	833.2	821.5	2,438.7	2,416.9
Income (Loss) from Operations	101.3	100.7	281.2	314.1
Depreciation and Amortization	31.6	34.5	91.3	94.2
Europe Paperboard Packaging | Operating Segments
Segment Reporting Information [Line Items]
Net Sales	152.6	142.1	431.0	435.3
Income (Loss) from Operations	10.2	6.9	26.2	25.3
Depreciation and Amortization	$ 10.4	$ 10.4	$ 30.3	$ 31.0