Segment reporting - Restructuring Asset Impairment and Acquisition Related Costs (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Segment Reporting Information [Line Items]
Restructuring, asset impairment and acquisition-related costs	$ 676,346	$ 271,397	$ 144,626
Operating segments | Consumer Packaging
Segment Reporting Information [Line Items]
Restructuring, asset impairment and acquisition-related costs	4,197	100,166	40,831
Operating segments | Industrial Paper Packaging
Segment Reporting Information [Line Items]
Restructuring, asset impairment and acquisition-related costs	(3,056)	33,450	5,491
Operating segments | All Other
Segment Reporting Information [Line Items]
Restructuring, asset impairment and acquisition-related costs	5,343	27,835	1,828
Corporate
Segment Reporting Information [Line Items]
Restructuring, asset impairment and acquisition-related costs	$ 669,862	$ 109,946	$ 96,476