Goodwill and Other Intangible Assets (Tables)

12 Months Ended

Dec. 31, 2025

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of Goodwill

Changes in the carrying amount of goodwill for the years ended December 31, 2025 and 2024 are as follows (dollars in thousands):

			Specialty
	Packaging		Products		Total
Balance, December 31, 2023	$	287,350	$	6,560	$	293,910
Foreign currency translation and other	(6,850)		—		(6,850)
Balance, December 31, 2024	$	280,500	$	6,560	$	287,060
Foreign currency translation and other	13,220		—		13,220
Balance, December 31, 2025	$	293,720	$	6,560	$	300,280
Accumulated impairment losses at December 31, 2025	$	58,660	$	—	$	58,660

Schedule of Intangible Assets (excluding Goodwill) by Major Class

The gross carrying amounts and accumulated amortization of the Company's other intangibles as of December 31, 2025 and 2024 are summarized below (dollars in thousands):

	As of December 31, 2025				As of December 31, 2024
Intangible Category by Useful Life	Gross Carrying Amount		Accumulated Amortization		Gross Carrying Amount		Accumulated Amortization
Finite-lived intangible assets:
Customer relationships, 5 - 12 years	$	99,270	$	(71,810)	$	95,110	$	(65,340)
Customer relationships, 15 - 25 years	39,280		(39,280)		39,280		(38,180)
Total customer relationships	138,550		(111,090)		134,390		(103,520)
Technology and other, 1 - 15 years	13,630		(12,140)		15,100		(13,500)
Technology and other, 17 - 30 years	41,600		(39,740)		41,600		(39,380)
Total technology and other	55,230		(51,880)		56,700		(52,880)
Indefinite-lived intangible assets:
Trademark/Trade names	45,740		—		43,700		—
Total other intangible assets	$	239,520	$	(162,970)	$	234,790	$	(156,400)

Schedule of Finite-Lived Intangible Assets, Amortization Expense

Amortization expense related to intangible assets as included in the accompanying consolidated statement of income is summarized as follows (dollars in thousands):

	Year ended December 31,
	2025		2024		2023
Technology and other, included in cost of sales	$	730	$	720	$	680
Customer relationships, included in selling, general and administrative expenses	5,950		5,800		6,160
Total amortization expense	$	6,680	$	6,520	$	6,840

Schedule of Expected Amortization Expense [Table Text Block]

Estimated amortization expense for the next five fiscal years beginning after December 31, 2025 is as follows (dollars in thousands):

Year ended December 31,	Estimated Amortization Expense
2026		$	5,200
2027		5,100
2028		5,080
2029		4,810
2030		4,570