Operating Segments and Geographic Information (Information About Reportable Segments) (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Segment Reporting Information [Line Items]
Net sales	$ 222,942	$ 226,863	$ 214,675	$ 214,611	$ 209,008	$ 206,783	$ 201,424	$ 203,828	$ 879,091	$ 821,043	$ 656,314
Operating income									112,711	129,139	80,897
Total assets	1,279,344				1,125,134				1,279,344	1,125,134	1,056,500
Capital expenditures									47,115	27,215	18,136
Capital expenditures, excluding ISOLA acquisition									90,549
Depreciation & amortization									50,073	44,099	37,847
Investment in unconsolidated joint ventures	18,667				18,324				18,667	18,324	16,183
Equity income in unconsolidated joint ventures									5,501	4,898	4,146
Advanced Connectivity Solutions
Segment Reporting Information [Line Items]
Net sales									294,154	301,092	277,787
Operating income									33,827	55,410	42,455
Total assets	396,075				353,786				396,075	353,786	361,746
Capital expenditures										9,900	7,569
Capital expenditures, excluding ISOLA acquisition									61,425
Depreciation & amortization									20,121	16,351	15,654
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									341,364	312,661	203,181
Operating income									52,502	50,908	25,884
Total assets	588,841				489,456				588,841	489,456	421,011
Capital expenditures										7,563	4,051
Capital expenditures, excluding ISOLA acquisition									10,917
Depreciation & amortization									18,501	16,270	10,141
Investment in unconsolidated joint ventures	18,667				18,324				18,667	18,324	16,183
Equity income in unconsolidated joint ventures									5,501	4,898	4,146
Power Electronics Solutions
Segment Reporting Information [Line Items]
Net sales									223,338	184,954	152,367
Operating income									19,648	15,668	5,229
Total assets	273,212				261,034				273,212	261,034	247,187
Capital expenditures										9,238	6,009
Capital expenditures, excluding ISOLA acquisition									18,051
Depreciation & amortization									10,640	10,572	11,208
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									20,235	22,336	22,979
Operating income									6,734	7,153	7,329
Total assets	21,216				20,858				21,216	20,858	26,556
Capital expenditures										514	507
Capital expenditures, excluding ISOLA acquisition									156
Depreciation & amortization									811	906	844
Investment in unconsolidated joint ventures	$ 0				$ 0				0	0	0
Equity income in unconsolidated joint ventures									0	$ 0	$ 0
Transferred over Time
Segment Reporting Information [Line Items]
Net sales									244,657
Transferred over Time | Advanced Connectivity Solutions
Segment Reporting Information [Line Items]
Net sales									0
Transferred over Time | Elastomeric Material Solutions
Segment Reporting Information [Line Items]
Net sales									5,788
Transferred over Time | Power Electronics Solutions
Segment Reporting Information [Line Items]
Net sales									221,896
Transferred over Time | Other
Segment Reporting Information [Line Items]
Net sales									16,973
Transferred at a point in time
Segment Reporting Information [Line Items]
Net sales									634,434
Transferred at a point in time | Advanced Connectivity Solutions
Segment Reporting Information [Line Items]
Net sales									294,154
Transferred at a point in time | Elastomeric Material Solutions
Segment Reporting Information [Line Items]
Net sales									335,576
Transferred at a point in time | Power Electronics Solutions
Segment Reporting Information [Line Items]
Net sales									1,442
Transferred at a point in time | Other
Segment Reporting Information [Line Items]
Net sales									$ 3,262