Acquisitions - Schedule of Acquisitions (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2018	Dec. 31, 2017
Business Acquisition [Line Items]
Goodwill	$ 888.7	$ 888.7	$ 883.2
Packaging
Business Acquisition [Line Items]
Goodwill	833.5	833.5	828.0
Sacramento Container Corporation
Business Acquisition [Line Items]
Other intangible assets	67.1	67.1	72.6
Property, plant and equipment	26.7	26.7	26.7
Other net assets	23.4	23.4	23.4
Net assets acquired	273.8	273.8	273.8
Goodwill, Adjustments		5.5
Other intangible assets, Adjustments	(5.5)	(5.5)
Sacramento Container Corporation \| Packaging
Business Acquisition [Line Items]
Goodwill	$ 156.6	$ 156.6	$ 151.1

Business combination, recognized identifiable assets acquired and liabilities assumed, net including goodwill.

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Amount of other assets expected to be realized or consumed after one year or the normal operating cycle, if longer, acquired at the acquisition date.

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- Definition

The amount of property, plant, and equipment recognized as of the acquisition date.

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Amount of increase (decrease) to assets, excluding financial assets and goodwill, lacking physical substance with a finite life for purchase accounting adjustments.

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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.

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