Operating Segment Information (Income by Reportable Segments) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Segment Reporting Information [Line Items]
Net sales	$ 198,810	$ 239,798
Operating income	17,475	32,800
Advanced Connectivity Solutions
Segment Reporting Information [Line Items]
Net sales	64,553	80,470
Operating income	5,462	13,064
Elastomeric Material Solutions
Segment Reporting Information [Line Items]
Net sales	83,526	92,762
Operating income	11,517	13,431
Power Electronics Solutions
Segment Reporting Information [Line Items]
Net sales	46,721	59,814
Operating income	(684)	4,267
Other
Segment Reporting Information [Line Items]
Net sales	4,010	6,752
Operating income	1,180	2,038
Recognized over time
Segment Reporting Information [Line Items]
Net sales	52,878	67,212
Recognized over time | Advanced Connectivity Solutions
Segment Reporting Information [Line Items]
Net sales	0	0
Recognized over time | Elastomeric Material Solutions
Segment Reporting Information [Line Items]
Net sales	2,827	3,006
Recognized over time | Power Electronics Solutions
Segment Reporting Information [Line Items]
Net sales	46,401	59,602
Recognized over time | Other
Segment Reporting Information [Line Items]
Net sales	3,650	4,604
Recognized at a point in time
Segment Reporting Information [Line Items]
Net sales	145,932	172,586
Recognized at a point in time | Advanced Connectivity Solutions
Segment Reporting Information [Line Items]
Net sales	64,553	80,470
Recognized at a point in time | Elastomeric Material Solutions
Segment Reporting Information [Line Items]
Net sales	80,699	89,756
Recognized at a point in time | Power Electronics Solutions
Segment Reporting Information [Line Items]
Net sales	320	212
Recognized at a point in time | Other
Segment Reporting Information [Line Items]
Net sales	360	2,148
United States
Segment Reporting Information [Line Items]
Net sales	62,171	65,303
United States | Advanced Connectivity Solutions
Segment Reporting Information [Line Items]
Net sales	14,453	13,071
United States | Elastomeric Material Solutions
Segment Reporting Information [Line Items]
Net sales	38,567	43,465
United States | Power Electronics Solutions
Segment Reporting Information [Line Items]
Net sales	8,172	7,477
United States | Other
Segment Reporting Information [Line Items]
Net sales	979	1,290
Other Americas
Segment Reporting Information [Line Items]
Net sales	3,813	3,046
Other Americas | Advanced Connectivity Solutions
Segment Reporting Information [Line Items]
Net sales	944	752
Other Americas | Elastomeric Material Solutions
Segment Reporting Information [Line Items]
Net sales	2,449	2,083
Other Americas | Power Electronics Solutions
Segment Reporting Information [Line Items]
Net sales	109	20
Other Americas | Other
Segment Reporting Information [Line Items]
Net sales	311	191
Total Americas
Segment Reporting Information [Line Items]
Net sales	65,984	68,349
Total Americas | Advanced Connectivity Solutions
Segment Reporting Information [Line Items]
Net sales	15,397	13,823
Total Americas | Elastomeric Material Solutions
Segment Reporting Information [Line Items]
Net sales	41,016	45,548
Total Americas | Power Electronics Solutions
Segment Reporting Information [Line Items]
Net sales	8,281	7,497
Total Americas | Other
Segment Reporting Information [Line Items]
Net sales	1,290	1,481
China
Segment Reporting Information [Line Items]
Net sales	51,533	78,485
China | Advanced Connectivity Solutions
Segment Reporting Information [Line Items]
Net sales	24,625	42,489
China | Elastomeric Material Solutions
Segment Reporting Information [Line Items]
Net sales	18,375	22,419
China | Power Electronics Solutions
Segment Reporting Information [Line Items]
Net sales	8,308	11,064
China | Other
Segment Reporting Information [Line Items]
Net sales	225	2,513
Other APAC
Segment Reporting Information [Line Items]
Net sales	33,180	34,776
Other APAC | Advanced Connectivity Solutions
Segment Reporting Information [Line Items]
Net sales	15,319	14,141
Other APAC | Elastomeric Material Solutions
Segment Reporting Information [Line Items]
Net sales	12,953	14,488
Other APAC | Power Electronics Solutions
Segment Reporting Information [Line Items]
Net sales	4,360	5,338
Other APAC | Other
Segment Reporting Information [Line Items]
Net sales	548	809
Total APAC
Segment Reporting Information [Line Items]
Net sales	84,713	113,261
Total APAC | Advanced Connectivity Solutions
Segment Reporting Information [Line Items]
Net sales	39,944	56,630
Total APAC | Elastomeric Material Solutions
Segment Reporting Information [Line Items]
Net sales	31,328	36,907
Total APAC | Power Electronics Solutions
Segment Reporting Information [Line Items]
Net sales	12,668	16,402
Total APAC | Other
Segment Reporting Information [Line Items]
Net sales	773	3,322
Germany
Segment Reporting Information [Line Items]
Net sales	20,512	30,001
Germany | Advanced Connectivity Solutions
Segment Reporting Information [Line Items]
Net sales	3,673	4,472
Germany | Elastomeric Material Solutions
Segment Reporting Information [Line Items]
Net sales	3,634	3,436
Germany | Power Electronics Solutions
Segment Reporting Information [Line Items]
Net sales	13,056	21,947
Germany | Other
Segment Reporting Information [Line Items]
Net sales	149	146
Other EMEA
Segment Reporting Information [Line Items]
Net sales	27,601	28,187
Other EMEA | Advanced Connectivity Solutions
Segment Reporting Information [Line Items]
Net sales	5,539	5,545
Other EMEA | Elastomeric Material Solutions
Segment Reporting Information [Line Items]
Net sales	7,548	6,871
Other EMEA | Power Electronics Solutions
Segment Reporting Information [Line Items]
Net sales	12,716	13,968
Other EMEA | Other
Segment Reporting Information [Line Items]
Net sales	1,798	1,803
Total EMEA
Segment Reporting Information [Line Items]
Net sales	48,113	58,188
Total EMEA | Advanced Connectivity Solutions
Segment Reporting Information [Line Items]
Net sales	9,212	10,017
Total EMEA | Elastomeric Material Solutions
Segment Reporting Information [Line Items]
Net sales	11,182	10,307
Total EMEA | Power Electronics Solutions
Segment Reporting Information [Line Items]
Net sales	25,772	35,915
Total EMEA | Other
Segment Reporting Information [Line Items]
Net sales	$ 1,947	$ 1,949