Segment Reporting - Segment Financial Information (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 27, 2015	Sep. 28, 2014	Sep. 27, 2015	Sep. 28, 2014
Segment Reporting Information [Line Items]
Net sales	$ 1,242,592	$ 1,262,503	$ 3,697,234	$ 3,700,151
Income before interest and income taxes	79,481	106,029	302,549	288,872
Restructuring/Asset impairment charges	(19,551)	(5,908)	(29,637)	(11,571)
Operating Segments [Member] \| Consumer Packaging [Member]
Segment Reporting Information [Line Items]
Net sales	521,499	479,609	1,572,490	1,418,200
Income before interest and income taxes	55,282	49,769	166,840	140,783
Operating Segments [Member] \| Paper And Industrial Converted Products [Member]
Segment Reporting Information [Line Items]
Net sales	427,753	480,741	1,298,940	1,426,367
Income before interest and income taxes	32,292	48,996	99,052	125,289
Operating Segments [Member] \| Display and Packaging [Member]
Segment Reporting Information [Line Items]
Net sales	162,945	177,364	450,334	497,543
Income before interest and income taxes	5,405	2,007	7,278	9,549
Operating Segments [Member] \| Protective Solutions [Member]
Segment Reporting Information [Line Items]
Net sales	130,395	124,789	375,470	358,041
Income before interest and income taxes	12,911	10,277	36,200	25,204
Intersegment Sales [Member]
Segment Reporting Information [Line Items]
Net sales	29,084	27,583	86,587	84,655
Intersegment Sales [Member] \| Consumer Packaging [Member]
Segment Reporting Information [Line Items]
Net sales	1,587	1,008	4,588	2,916
Intersegment Sales [Member] \| Paper And Industrial Converted Products [Member]
Segment Reporting Information [Line Items]
Net sales	26,243	25,824	78,832	78,822
Intersegment Sales [Member] \| Display and Packaging [Member]
Segment Reporting Information [Line Items]
Net sales	523	385	1,371	1,165
Intersegment Sales [Member] \| Protective Solutions [Member]
Segment Reporting Information [Line Items]
Net sales	731	366	1,796	1,752
Segment Reconciling Items [Member]
Segment Reporting Information [Line Items]
Restructuring/Asset impairment charges	(19,551)	(5,908)	(29,637)	(11,571)
Other, net	$ (6,858)	$ 888	22,816	$ (382)
Operating Units 2 - 5 [Member]
Segment Reporting Information [Line Items]
Decrease due to revision of estimates			$ 32,543

The Increase or Decrease in the accrual for environmental loss in the period from revisions in estimates to existing obligations. The amount does not relate to changes in the environmental accrual related to business acquisitions or divestitures, or to currency movements.

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