Restructuring and Asset Impairment - Restructuring and Restructuring-related Asset Impairment Expenses by Type Incurred and by Reportable Segment (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 28, 2020	Jun. 30, 2019	Jun. 28, 2020	Jun. 30, 2019
Restructuring Cost and Reserve [Line Items]
Total Restructuring/Asset Impairment Charges	$ 22,885	$ 13,355	$ 35,484	$ 24,027
Severance and Termination Benefits
Restructuring Cost and Reserve [Line Items]
Total Restructuring/Asset Impairment Charges	15,159	5,199	25,259	11,499
Severance and Termination Benefits | Operating Segments | Consumer Packaging
Restructuring Cost and Reserve [Line Items]
Total Restructuring/Asset Impairment Charges	3,250	10,487	5,612	17,742
Severance and Termination Benefits | Operating Segments | Display and Packaging
Restructuring Cost and Reserve [Line Items]
Total Restructuring/Asset Impairment Charges	668	511	3,548	886
Severance and Termination Benefits | Operating Segments | Paper and Industrial Converted Products
Restructuring Cost and Reserve [Line Items]
Total Restructuring/Asset Impairment Charges	17,689	1,600	23,045	2,474
Severance and Termination Benefits | Operating Segments | Protective Solutions
Restructuring Cost and Reserve [Line Items]
Total Restructuring/Asset Impairment Charges	695	561	1,168	1,003
Asset Impairment/ Disposal of Assets
Restructuring Cost and Reserve [Line Items]
Total Restructuring/Asset Impairment Charges	6,073	5,652	8,759	7,284
Other Costs
Restructuring Cost and Reserve [Line Items]
Total Restructuring/Asset Impairment Charges	1,653	2,504	1,466	5,244
Other Costs | Corporate
Restructuring Cost and Reserve [Line Items]
Total Restructuring/Asset Impairment Charges	$ 583	$ 196	$ 2,111	$ 1,922