Segment Reporting - Segment Reporting (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 27, 2025	Jun. 28, 2024	Jun. 27, 2025	Jun. 28, 2024
Segment Reporting Information [Line Items]
Net sales	$ 431,658	$ 425,866	$ 851,988	$ 811,153
Cost of sales	349,000	345,007	693,151	659,082
Selling, general, and administrative expense	35,039	33,601	70,484	69,445
Other segment items	10,233	14,556	23,106	27,032
Segment depreciation, depletion and amortization	17,509	16,513	34,047	32,698
Segment EBITDA	54,895	49,215	99,294	88,292
Income tax expense	4,016	4,864	7,262	6,068
Interest expense - net	8,230	8,802	15,147	17,081
Net income	25,140	19,036	42,838	32,445
Performance Materials
Segment Reporting Information [Line Items]
Net sales	182,778	187,513	356,765	356,158
Cost of sales	133,770	138,784	259,526	267,348
Selling, general, and administrative expense	14,242	13,143	28,223	27,298
Other segment items	3,864	3,845	6,871	7,283
Segment depreciation, depletion and amortization	10,192	8,674	19,622	16,862
Segment EBITDA	41,094	40,415	81,767	71,091
Electronic Materials
Segment Reporting Information [Line Items]
Net sales	224,427	212,687	449,222	404,658
Cost of sales	197,166	187,592	398,223	354,507
Selling, general, and administrative expense	9,125	9,584	19,744	19,715
Other segment items	4,796	6,601	11,104	11,741
Segment depreciation, depletion and amortization	4,261	4,546	8,528	9,114
Segment EBITDA	17,601	13,456	28,679	27,809
Precision Optics
Segment Reporting Information [Line Items]
Net sales	24,453	25,666	46,001	50,337
Cost of sales	17,995	18,623	35,319	37,208
Selling, general, and administrative expense	4,316	4,905	8,702	10,519
Other segment items	2,603	3,372	6,278	7,001
Segment depreciation, depletion and amortization	2,560	2,823	4,915	5,727
Segment EBITDA	2,099	1,589	617	1,336
Other
Segment Reporting Information [Line Items]
Net sales	0	0	0	0
Cost of sales	69	8	83	19
Selling, general, and administrative expense	7,356	5,969	13,815	11,913
Other segment items	(1,030)	738	(1,147)	1,007
Segment depreciation, depletion and amortization	496	470	982	995
Segment EBITDA	$ (5,899)	$ (6,245)	$ (11,769)	$ (11,944)