Operating Segments and Geographic Information (Revenue by Country) (Details) - 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
Disaggregation of Revenue [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
Advanced Connectivity Solutions
Disaggregation of Revenue [Line Items]
Net sales									268,699	316,592	294,154
Elastomeric Material Solutions
Disaggregation of Revenue [Line Items]
Net sales									328,177	361,603	341,364
Power Electronics Solutions
Disaggregation of Revenue [Line Items]
Net sales									189,980	198,535	223,338
Other
Disaggregation of Revenue [Line Items]
Net sales									15,727	21,530	20,235
Total Americas
Disaggregation of Revenue [Line Items]
Net sales									234,910	274,886	266,058
Total Americas | Advanced Connectivity Solutions
Disaggregation of Revenue [Line Items]
Net sales									69,050	67,101	55,765
Total Americas | Elastomeric Material Solutions
Disaggregation of Revenue [Line Items]
Net sales									136,784	170,126	166,737
Total Americas | Power Electronics Solutions
Disaggregation of Revenue [Line Items]
Net sales									24,715	32,239	38,256
Total Americas | Other
Disaggregation of Revenue [Line Items]
Net sales									4,361	5,420	5,300
United States
Disaggregation of Revenue [Line Items]
Net sales									222,848	261,052	246,797
United States | Advanced Connectivity Solutions
Disaggregation of Revenue [Line Items]
Net sales									66,411	63,753	52,661
United States | Elastomeric Material Solutions
Disaggregation of Revenue [Line Items]
Net sales									128,347	160,918	152,284
United States | Power Electronics Solutions
Disaggregation of Revenue [Line Items]
Net sales									24,411	31,874	37,325
United States | Other
Disaggregation of Revenue [Line Items]
Net sales									3,679	4,507	4,527
Other Americas
Disaggregation of Revenue [Line Items]
Net sales									12,062	13,834	19,261
Other Americas | Advanced Connectivity Solutions
Disaggregation of Revenue [Line Items]
Net sales									2,639	3,348	3,104
Other Americas | Elastomeric Material Solutions
Disaggregation of Revenue [Line Items]
Net sales									8,437	9,208	14,453
Other Americas | Power Electronics Solutions
Disaggregation of Revenue [Line Items]
Net sales									304	365	931
Other Americas | Other
Disaggregation of Revenue [Line Items]
Net sales									682	913	773
Total APAC
Disaggregation of Revenue [Line Items]
Net sales									380,673	437,437	417,503
Total APAC | Advanced Connectivity Solutions
Disaggregation of Revenue [Line Items]
Net sales									167,196	213,584	199,633
Total APAC | Elastomeric Material Solutions
Disaggregation of Revenue [Line Items]
Net sales									151,525	151,055	141,824
Total APAC | Power Electronics Solutions
Disaggregation of Revenue [Line Items]
Net sales									56,931	63,792	68,195
Total APAC | Other
Disaggregation of Revenue [Line Items]
Net sales									5,021	9,006	7,851
China
Disaggregation of Revenue [Line Items]
Net sales									264,317	295,257	282,091
China | Advanced Connectivity Solutions
Disaggregation of Revenue [Line Items]
Net sales									115,454	153,127	136,315
China | Elastomeric Material Solutions
Disaggregation of Revenue [Line Items]
Net sales									108,161	95,653	101,036
China | Power Electronics Solutions
Disaggregation of Revenue [Line Items]
Net sales									37,843	40,391	39,781
China | Other
Disaggregation of Revenue [Line Items]
Net sales									2,859	6,086	4,959
Other APAC
Disaggregation of Revenue [Line Items]
Net sales									116,356	142,180	135,412
Other APAC | Advanced Connectivity Solutions
Disaggregation of Revenue [Line Items]
Net sales									51,742	60,457	63,318
Other APAC | Elastomeric Material Solutions
Disaggregation of Revenue [Line Items]
Net sales									43,364	55,402	40,788
Other APAC | Power Electronics Solutions
Disaggregation of Revenue [Line Items]
Net sales									19,088	23,401	28,414
Other APAC | Other
Disaggregation of Revenue [Line Items]
Net sales									2,162	2,920	2,892
Total EMEA
Disaggregation of Revenue [Line Items]
Net sales									187,000	185,937	195,530
Total EMEA | Advanced Connectivity Solutions
Disaggregation of Revenue [Line Items]
Net sales									32,453	35,907	38,756
Total EMEA | Elastomeric Material Solutions
Disaggregation of Revenue [Line Items]
Net sales									39,868	40,422	32,803
Total EMEA | Power Electronics Solutions
Disaggregation of Revenue [Line Items]
Net sales									108,334	102,504	116,887
Total EMEA | Other
Disaggregation of Revenue [Line Items]
Net sales									6,345	7,104	7,084
Germany
Disaggregation of Revenue [Line Items]
Net sales									90,409	87,948	91,015
Germany | Advanced Connectivity Solutions
Disaggregation of Revenue [Line Items]
Net sales									11,452	15,912	18,165
Germany | Elastomeric Material Solutions
Disaggregation of Revenue [Line Items]
Net sales									19,118	13,702	9,907
Germany | Power Electronics Solutions
Disaggregation of Revenue [Line Items]
Net sales									59,429	57,761	62,359
Germany | Other
Disaggregation of Revenue [Line Items]
Net sales									410	573	584
Other EMEA
Disaggregation of Revenue [Line Items]
Net sales									96,591	97,989	104,515
Other EMEA | Advanced Connectivity Solutions
Disaggregation of Revenue [Line Items]
Net sales									21,001	19,995	20,591
Other EMEA | Elastomeric Material Solutions
Disaggregation of Revenue [Line Items]
Net sales									20,750	26,720	22,896
Other EMEA | Power Electronics Solutions
Disaggregation of Revenue [Line Items]
Net sales									48,905	44,743	54,528
Other EMEA | Other
Disaggregation of Revenue [Line Items]
Net sales									$ 5,935	$ 6,531	$ 6,500