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	$ 1,640.1	$ 1,484.0	$ 4,760.6	$ 4,302.4
Operating income (loss)	242.3	206.4	679.2	587.4
Interest expense, net	(25.4)	(23.4)	(74.6)	(67.5)
Income before taxes	216.9	183.0	604.6	519.9
Intersegment Eliminations
Segment Reporting Information [Line Items]
Net sales	(39.0)	(38.8)	(109.9)	(111.2)
Segment Reconciling Items
Segment Reporting Information [Line Items]
Net sales	(39.0)	(38.8)	(109.9)	(111.2)
Packaging
Segment Reporting Information [Line Items]
Net sales	1,340.6	1,165.0	3,897.4	3,382.4
Operating income (loss)	261.5	179.6	676.8	533.5
Packaging \| Intersegment Eliminations
Segment Reporting Information [Line Items]
Net sales	6.0	2.1	17.6	5.5
Packaging \| Operating Segments
Segment Reporting Information [Line Items]
Net sales	1,346.6	1,167.1	3,915.0	3,387.9
Paper
Segment Reporting Information [Line Items]
Net sales	271.4	292.8	784.3	840.1
Operating income (loss)	(0.7)	44.5	58.1	105.0
Paper \| Operating Segments
Segment Reporting Information [Line Items]
Net sales	271.4	292.8	784.3	840.1
Corporate and Other Segment
Segment Reporting Information [Line Items]
Net sales	28.1	26.2	78.9	79.9
Operating income (loss)	(18.5)	(17.7)	(55.7)	(51.1)
Corporate and Other Segment \| Intersegment Eliminations
Segment Reporting Information [Line Items]
Net sales	33.0	36.7	92.3	105.7
Corporate and Other Segment \| Operating Segments
Segment Reporting Information [Line Items]
Net sales	$ 61.1	$ 62.9	$ 171.2	$ 185.6

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 940
-SubTopic 20
-Section 25
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=68072869&loc=d3e41242-110953

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(10))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(15))
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(8))
-URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913

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