Segment Reporting - Segment Activity (Details) - USD ($) $ in Thousands		3 Months Ended					12 Months Ended
		Mar. 31, 2026		Sep. 30, 2025	Mar. 31, 2025		Dec. 31, 2025	Dec. 31, 2024
Segment Reporting Information [Line Items]
Net sales		$ 168,280			$ 152,460
Cost of sales		(131,410)			(119,630)
Selling, general and administrative expenses		(29,990)			(30,970)
Segment adjusted operating profit		17,410			16,090
Operating profit (loss)		6,890			7,150
Interest expense		(5,240)			(4,520)
Other income (expense), net		890			(40)
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest		2,540			2,590
Net gain on dispositions of assets		10			5,290
Asbestos-related costs		0			0
Payments to Acquire Productive Assets		5,220			12,940
Depreciation, Depletion and Amortization		9,630			9,230
Assets		2,297,130					$ 1,485,080
Cash and cash equivalents		1,309,610					30,020
Outside basis difference on held for sale assets							53,900
Continuing Operations [Member]
Segment Reporting Information [Line Items]
Segment, Expenditure, Addition to Long-Lived Assets		5,680			10,450
Assets		2,297,130					1,041,630
Asbestos [Member]
Segment Reporting Information [Line Items]
Asbestos-related costs							8,000
Loss Contingency, Receivable		34,280			0		34,700	$ 0
Arrow Engine
Segment Reporting Information [Line Items]
Net gain on dispositions of assets				$ 100	5,300
Packaging [Member]
Segment Reporting Information [Line Items]
Net sales		139,170			127,570
Cost of sales		(106,510)			(96,110)
Selling, general and administrative expenses		(18,100)			(14,210)
Segment Reporting, Other Segment Item, Amount	[1]	(10)			(10)
Segment adjusted operating profit		14,550			17,240
Segment, Expenditure, Addition to Long-Lived Assets		3,760			7,980
Depreciation, Depletion and Amortization		8,790			8,330
Assets		861,290					855,080
Corporate Segment
Segment Reporting Information [Line Items]
Operating profit (loss)		(10,520)	[2]		(8,940)	[3]
Realignment and severance costs		(1,400)			(4,700)
System implementation costs		(1,200)			(900)
Mergers, acquisitions, diligence and transaction costs					(300)
Segment, Expenditure, Addition to Long-Lived Assets		490			1,410
Depreciation, Depletion and Amortization		110			80
Assets		1,348,890					112,660
Cash and cash equivalents		1,282,300
Specialty Products [Member]
Segment Reporting Information [Line Items]
Net sales		29,110			24,890
Cost of sales		(24,900)			(23,520)
Selling, general and administrative expenses		(1,370)			(2,520)
Segment Reporting, Other Segment Item, Amount	[1]	20			0
Segment adjusted operating profit		2,860			(1,150)
Segment, Expenditure, Addition to Long-Lived Assets		1,430			1,060
Depreciation, Depletion and Amortization		730			$ 820
Assets		$ 86,950					$ 73,890

[1] Other segment items for each reportable segment includes net gain (loss) on dispositions of assets.

[2] Includes $1.4 million of realignment and severance costs and $1.2 million of system implementation costs

[3] Includes $5.3 million gain on the sale of Arrow Engine, $4.7 million of realignment, severance and consulting costs, $0.9 million of system implementation costs and $0.3 million of mergers, acquisition, diligence and transaction costs