Summary of significant accounting policies (Tables)

12 Months Ended

Dec. 31, 2019

Accounting Policies [Abstract]

Affiliated companies over which the Company exercised significant influence

Affiliated companies over which the Company exercised a significant influence at December 31, 2019, included:

Entity	Ownership Interest Percentage at December 31, 2019
RTS Packaging JVCO	35.0	%
Cascades Conversion, Inc.	50.0	%
Cascades Sonoco, Inc.	50.0	%
Showa Products Company Ltd.	22.2	%
Crown Fibre Tube. Inc.	20.0	%
Papertech Energía, S.L.	25.0	%
Weidenhammer New Packaging, LLC	40.0	%