Goodwill and other intangible assets - Changes in Goodwill by Segment (Details) $ in Thousands	12 Months Ended
Dec. 31, 2019 USD ($)
Goodwill [Roll Forward]
Balance as of January 1, 2019	$ 1,309,167
Acquisitions	119,022
Measurement period adjustments	(215)
Foreign currency translation	1,372
Balance as of December 31, 2019	1,429,346
Consumer Packaging
Goodwill [Roll Forward]
Balance as of January 1, 2019	617,332
Acquisitions	75,595
Measurement period adjustments	(2,461)
Foreign currency translation	777
Balance as of December 31, 2019	691,243
Display and Packaging
Goodwill [Roll Forward]
Balance as of January 1, 2019	203,414
Acquisitions	0
Measurement period adjustments	0
Foreign currency translation	0
Balance as of December 31, 2019	203,414
Paper and Industrial Converted Products
Goodwill [Roll Forward]
Balance as of January 1, 2019	256,947
Acquisitions	43,427
Measurement period adjustments	2,246
Foreign currency translation	421
Balance as of December 31, 2019	303,041
Protective Solutions
Goodwill [Roll Forward]
Balance as of January 1, 2019	231,474
Acquisitions	0
Measurement period adjustments
Foreign currency translation	174
Balance as of December 31, 2019	$ 231,648

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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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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