Segment Reporting - Schedule of Segment Financial Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 29, 2024	Oct. 01, 2023	Sep. 29, 2024	Oct. 01, 2023
Segment Reporting Information [Line Items]
Net sales	$ 1,675,866	$ 1,710,419	$ 4,936,888	$ 5,145,492
Operating profit	128,132	162,937	380,957	580,444
Restructuring/Asset impairment charges	(8,190)	(18,110)	(59,058)	(52,981)
Amortization of acquisition intangibles	(22,645)	(21,379)	(68,095)	(63,082)
(Loss)/Gain on divestiture of business and other assets	(31,770)	(537)	(27,292)	78,844
Acquisition, integration and divestiture-related costs	(19,623)	(12,472)	(47,553)	(22,192)
Changes in LIFO inventory reserves	(790)	3,186	197	10,186
Net gains from derivatives	210	3,308	3,981	1,513
Other operating income/(charges), net	273	(3,605)	(851)	(8,750)
Other income, net	0	36,943	5,867	36,943
Non-operating pension costs	(2,947)	(3,424)	(10,412)	(10,424)
Interest expense	(61,643)	(32,847)	(122,503)	(101,363)
Interest income	6,014	3,173	13,127	6,679
Income before income taxes	69,556	166,782	267,036	512,279
Acquisition, integration and divestiture-related costs	49,804	12,472	77,734	22,192
Interest Expense
Segment Reporting Information [Line Items]
Acquisition, integration and divestiture-related costs	30,181		30,181
Intersegment sales
Segment Reporting Information [Line Items]
Net sales	32,716	7,528	99,744	90,664
Operating Segments
Segment Reporting Information [Line Items]
Net sales	1,568,593	1,564,875	4,600,729	4,695,201
Operating profit	193,227	191,806	531,198	570,821
Operating Segments | Intersegment sales
Segment Reporting Information [Line Items]
Net sales	30,841	5,788	94,219	84,290
Operating Segments | Consumer Packaging
Segment Reporting Information [Line Items]
Net sales	983,511	984,840	2,821,817	2,914,168
Operating profit	123,021	116,800	328,190	314,408
Operating Segments | Consumer Packaging | Intersegment sales
Segment Reporting Information [Line Items]
Net sales	4,163	2,756	12,237	7,127
Operating Segments | Industrial Paper Packaging
Segment Reporting Information [Line Items]
Net sales	585,082	580,035	1,778,912	1,781,033
Operating profit	70,206	75,006	203,008	256,413
Operating Segments | Industrial Paper Packaging | Intersegment sales
Segment Reporting Information [Line Items]
Net sales	26,678	3,032	81,982	77,163
All Other
Segment Reporting Information [Line Items]
Net sales	107,273	145,544	336,159	450,291
Operating profit	17,440	20,740	48,430	66,085
All Other | Intersegment sales
Segment Reporting Information [Line Items]
Net sales	$ 1,875	$ 1,740	$ 5,525	$ 6,374