Divestitures and Acquisitions - Acquisitions Narrative (Details) - USD ($)			2 Months Ended	3 Months Ended		9 Months Ended
	Aug. 01, 2019	Aug. 01, 2018	Sep. 30, 2019	Sep. 30, 2019	Jun. 30, 2019	Sep. 30, 2019	Dec. 31, 2018
Business Acquisition [Line Items]
Goodwill			$ 2,213,100,000	$ 2,213,100,000		$ 2,213,100,000	$ 1,947,600,000
Product Care
Business Acquisition [Line Items]
Goodwill			1,691,300,000	1,691,300,000		1,691,300,000	$ 1,427,900,000
Automated Packaging Systems
Business Acquisition [Line Items]
Percentage of shares acquired	100.00%
Consideration transferred	$ 445,700,000
Acquisition transaction costs				300,000		2,800,000
Indefinite-lived intangible assets	0
Goodwill	$ 261,300,000
Automated Packaging Systems | Backlog
Business Acquisition [Line Items]
Useful life of intangible assets acquired	1 year
Automated Packaging Systems | Minimum
Business Acquisition [Line Items]
Useful life of intangible assets acquired	5 years
Automated Packaging Systems | Maximum
Business Acquisition [Line Items]
Useful life of intangible assets acquired	15 years
Automated Packaging Systems | APS European Employees
Business Acquisition [Line Items]
Liabilities assumed	$ 58,200,000
Payments to deferred compensation plan equal installment period	3 years
Other Acquisitions
Business Acquisition [Line Items]
Cash paid to acquire business					$ 23,400,000
Goodwill					$ 6,000,000.0
Goodwill adjustment				300,000
AFP
Business Acquisition [Line Items]
Consideration transferred		$ 70,800,000	3,300,000			74,100,000
Goodwill		$ 21,600,000	22,600,000	$ 22,600,000		$ 22,600,000
Goodwill adjustment			$ 1,000,000.0
AFP | Product Care
Business Acquisition [Line Items]
Percentage of shares acquired		100.00%
Consideration transferred		$ 74,100,000
Cash acquired from acquisition		$ 3,300,000