Operating Segments and Geographic Information (Information About Reportable Segments) (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Segment Reporting Information [Line Items]
Net sales	$ 210,672	$ 201,944	$ 191,157	$ 198,810	$ 193,768	$ 221,842	$ 242,852	$ 239,798	$ 802,583	$ 898,260	$ 879,091
Operating income (loss)									67,334	110,481	112,711
Total assets	1,264,005				1,273,181				1,264,005	1,273,181	1,279,344
Capital expenditures									40,385	51,597	90,549
Depreciation & amortization									71,425	49,162	50,073
Investment in unconsolidated joint ventures	15,248				16,461				15,248	16,461	18,667
Equity income in unconsolidated joint ventures									4,877	5,319	5,501
Advanced Connectivity Solutions
Segment Reporting Information [Line Items]
Net sales									268,699	316,592	294,154
Operating income (loss)									38,202	48,654	33,827
Total assets	407,667				402,398				407,667	402,398	396,075
Capital expenditures									11,849	22,156	61,425
Depreciation & amortization									13,762	18,267	20,121
Investment in unconsolidated joint ventures	0				0				0	0	0
Equity income in unconsolidated joint ventures									0	0	0
Elastomeric Material Solutions
Segment Reporting Information [Line Items]
Net sales									328,177	361,603	341,364
Operating income (loss)									30,817	57,080	52,502
Total assets	504,199				569,484				504,199	569,484	588,841
Capital expenditures									16,214	8,550	10,917
Depreciation & amortization									47,159	19,887	18,501
Investment in unconsolidated joint ventures	15,248				16,461				15,248	16,461	18,667
Equity income in unconsolidated joint ventures									4,877	5,319	5,501
Power Electronics Solutions
Segment Reporting Information [Line Items]
Net sales									189,980	198,535	223,338
Operating income (loss)									(6,179)	(1,437)	19,648
Total assets	338,419				278,763				338,419	278,763	273,212
Capital expenditures									11,840	20,191	18,051
Depreciation & amortization									9,831	10,260	10,640
Investment in unconsolidated joint ventures	0				0				0	0	0
Equity income in unconsolidated joint ventures									0	0	0
Other
Segment Reporting Information [Line Items]
Net sales									15,727	21,530	20,235
Operating income (loss)									4,494	6,184	6,734
Total assets	13,720				22,536				13,720	22,536	21,216
Capital expenditures									482	700	156
Depreciation & amortization									673	748	811
Investment in unconsolidated joint ventures	$ 0				$ 0				0	0	0
Equity income in unconsolidated joint ventures									0	0	0
Recognized over time
Segment Reporting Information [Line Items]
Net sales									215,107	228,501	244,657
Recognized over time | Advanced Connectivity Solutions
Segment Reporting Information [Line Items]
Net sales									902	0	0
Recognized over time | Elastomeric Material Solutions
Segment Reporting Information [Line Items]
Net sales									10,614	12,687	5,788
Recognized over time | Power Electronics Solutions
Segment Reporting Information [Line Items]
Net sales									189,140	197,702	221,896
Recognized over time | Other
Segment Reporting Information [Line Items]
Net sales									14,451	18,112	16,973
Recognized at a point in time
Segment Reporting Information [Line Items]
Net sales									587,476	669,759	634,434
Recognized at a point in time | Advanced Connectivity Solutions
Segment Reporting Information [Line Items]
Net sales									267,797	316,592	294,154
Recognized at a point in time | Elastomeric Material Solutions
Segment Reporting Information [Line Items]
Net sales									317,563	348,916	335,576
Recognized at a point in time | Power Electronics Solutions
Segment Reporting Information [Line Items]
Net sales									840	833	1,442
Recognized at a point in time | Other
Segment Reporting Information [Line Items]
Net sales									$ 1,276	$ 3,418	$ 3,262