Segment Reporting - Segment Financial Information (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 29, 2020	Mar. 31, 2019
Segment Reporting Information [Line Items]
Net sales	$ 1,303,296	$ 1,351,705
Operating profit	130,103	116,888
Restructuring/Asset impairment charges	(12,599)	(10,672)
Consumer Packaging
Segment Reporting Information [Line Items]
Net sales	588,417	589,716
Display and Packaging
Segment Reporting Information [Line Items]
Net sales	121,356	137,554
Paper and Industrial Converted Products
Segment Reporting Information [Line Items]
Net sales	474,970	496,037
Protective Solutions
Segment Reporting Information [Line Items]
Net sales	118,553	128,398
Operating Segments \| Consumer Packaging
Segment Reporting Information [Line Items]
Net sales	588,417	589,716
Operating profit	67,801	62,115
Operating Segments \| Display and Packaging
Segment Reporting Information [Line Items]
Net sales	121,356	137,554
Operating profit	8,094	6,454
Operating Segments \| Paper and Industrial Converted Products
Segment Reporting Information [Line Items]
Net sales	474,970	496,037
Operating profit	54,013	48,387
Operating Segments \| Protective Solutions
Segment Reporting Information [Line Items]
Net sales	118,553	128,398
Operating profit	14,004	11,004
Intersegment Sales
Segment Reporting Information [Line Items]
Net sales	33,155	36,204
Intersegment Sales \| Consumer Packaging
Segment Reporting Information [Line Items]
Net sales	2,273	921
Intersegment Sales \| Display and Packaging
Segment Reporting Information [Line Items]
Net sales	1,298	1,167
Intersegment Sales \| Paper and Industrial Converted Products
Segment Reporting Information [Line Items]
Net sales	29,212	33,654
Intersegment Sales \| Protective Solutions
Segment Reporting Information [Line Items]
Net sales	372	462
Segment Reconciling Items
Segment Reporting Information [Line Items]
Other, net	$ (1,210)	$ (400)

The net result for the period of deducting operating expenses from operating revenues.

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- Definition

The total amount of other operating cost and expense items that are associated with the entity's normal revenue producing operation.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.3)
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- Definition

Amount, after cash payment, of expenses associated with exit or disposal activities pursuant to an authorized plan and expenses resulting from the write-down of assets. Excludes expenses related to a business combination, a discontinued operation or an asset retirement obligation.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130543-203045

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130545-203045

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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