Business Segments - Schedule of Financial Information for Corporation's Reportable Segments (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales	$ 102,918	$ 113,104	$ 211,245	$ 217,369
Costs of products sold (excluding depreciation and amortization)	80,675	91,981	167,430	174,085
Selling and administrative	12,917	12,968	26,801	26,627
Depreciation and amortization	4,226	5,368	8,484	10,004
Deconsolidation Charge			875
Severance charge		5,854		5,854
Income (loss) from operations	5,072	(3,078)	7,634	772
Reconciliation to income (loss) before income taxes
Interest expense	(2,791)	(2,825)	(5,514)	(5,551)
Income (loss) before income taxes	2,826	(6,128)	3,261	(4,178)
Operating Segments
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales	102,918	113,104	211,245	217,369
Income (loss) from operations	8,839	(41)	15,137	7,358
Operating Segments | FCEP
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales	67,311	77,909	138,120	150,196
Costs of products sold (excluding depreciation and amortization)	54,215	64,437	113,406	122,050
Selling and administrative	5,284	6,486	11,204	12,871
Depreciation and amortization	3,863	5,084	7,787	9,452
Deconsolidation Charge			875
Severance charge		5,854		5,854
Loss on disposal of assets	28	11	21	27
Income (loss) from operations	3,921	(3,963)	4,827	(58)
Operating Segments | ALP
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales	35,607	35,195	73,125	67,173
Costs of products sold (excluding depreciation and amortization)	26,460	27,544	54,024	52,035
Selling and administrative	3,879	3,445	8,114	7,170
Depreciation and amortization	350	284	677	552
Income (loss) from operations	4,918	3,922	10,310	7,416
Reconciling Item, Excluding Corporate Nonsegment
Reconciliation to income (loss) before income taxes
Interest expense	(2,791)	(2,825)	(5,514)	(5,551)
Other income (expense) - net	545	(225)	1,141	601
Corporate Nonsegment
Revenues from External Customers and Long-Lived Assets [Line Items]
Depreciation and amortization	13		20
Reconciliation to income (loss) before income taxes
Corporate costs	$ (3,767)	$ (3,037)	$ (7,503)	$ (6,586)