Operating Segments and Geographic Information (Revenue by Country) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disaggregation of Revenue [Line Items]
Net sales	$ 193,768	$ 221,842	$ 242,852	$ 239,798	$ 222,942	$ 226,863	$ 214,675	$ 214,611	$ 898,260	$ 879,091	$ 821,043
Advanced Connectivity Solutions
Disaggregation of Revenue [Line Items]
Net sales									316,592	294,154	301,092
Elastomeric Material Solutions
Disaggregation of Revenue [Line Items]
Net sales									361,603	341,364	312,661
Power Electronics Solutions
Disaggregation of Revenue [Line Items]
Net sales									198,535	223,338	184,954
Other
Disaggregation of Revenue [Line Items]
Net sales									21,530	20,235	22,336
United States
Disaggregation of Revenue [Line Items]
Net sales									261,052	246,797	225,398
United States | Advanced Connectivity Solutions
Disaggregation of Revenue [Line Items]
Net sales									63,753	52,661	48,277
United States | Elastomeric Material Solutions
Disaggregation of Revenue [Line Items]
Net sales									160,918	152,284	141,508
United States | Power Electronics Solutions
Disaggregation of Revenue [Line Items]
Net sales									31,874	37,325	30,403
United States | Other
Disaggregation of Revenue [Line Items]
Net sales									4,507	4,527	5,210
Other Americas
Disaggregation of Revenue [Line Items]
Net sales									13,834	19,261	14,507
Other Americas | Advanced Connectivity Solutions
Disaggregation of Revenue [Line Items]
Net sales									3,348	3,104	2,946
Other Americas | Elastomeric Material Solutions
Disaggregation of Revenue [Line Items]
Net sales									9,208	14,453	9,709
Other Americas | Power Electronics Solutions
Disaggregation of Revenue [Line Items]
Net sales									365	931	1,153
Other Americas | Other
Disaggregation of Revenue [Line Items]
Net sales									913	773	699
Total Americas
Disaggregation of Revenue [Line Items]
Net sales									274,886	266,058	239,905
Total Americas | Advanced Connectivity Solutions
Disaggregation of Revenue [Line Items]
Net sales									67,101	55,765	51,223
Total Americas | Elastomeric Material Solutions
Disaggregation of Revenue [Line Items]
Net sales									170,126	166,737	151,217
Total Americas | Power Electronics Solutions
Disaggregation of Revenue [Line Items]
Net sales									32,239	38,256	31,556
Total Americas | Other
Disaggregation of Revenue [Line Items]
Net sales									5,420	5,300	5,909
China
Disaggregation of Revenue [Line Items]
Net sales									295,257	282,091	273,391
China | Advanced Connectivity Solutions
Disaggregation of Revenue [Line Items]
Net sales									153,127	136,315	143,065
China | Elastomeric Material Solutions
Disaggregation of Revenue [Line Items]
Net sales									95,653	101,036	93,039
China | Power Electronics Solutions
Disaggregation of Revenue [Line Items]
Net sales									40,391	39,781	32,164
China | Other
Disaggregation of Revenue [Line Items]
Net sales									6,086	4,959	5,123
Other APAC
Disaggregation of Revenue [Line Items]
Net sales									142,180	135,412	125,576
Other APAC | Advanced Connectivity Solutions
Disaggregation of Revenue [Line Items]
Net sales									60,457	63,318	64,077
Other APAC | Elastomeric Material Solutions
Disaggregation of Revenue [Line Items]
Net sales									55,402	40,788	36,233
Other APAC | Power Electronics Solutions
Disaggregation of Revenue [Line Items]
Net sales									23,401	28,414	21,845
Other APAC | Other
Disaggregation of Revenue [Line Items]
Net sales									2,920	2,892	3,421
Total APAC
Disaggregation of Revenue [Line Items]
Net sales									437,437	417,503	398,967
Total APAC | Advanced Connectivity Solutions
Disaggregation of Revenue [Line Items]
Net sales									213,584	199,633	207,142
Total APAC | Elastomeric Material Solutions
Disaggregation of Revenue [Line Items]
Net sales									151,055	141,824	129,272
Total APAC | Power Electronics Solutions
Disaggregation of Revenue [Line Items]
Net sales									63,792	68,195	54,009
Total APAC | Other
Disaggregation of Revenue [Line Items]
Net sales									9,006	7,851	8,544
Germany
Disaggregation of Revenue [Line Items]
Net sales									87,948	91,015	88,606
Germany | Advanced Connectivity Solutions
Disaggregation of Revenue [Line Items]
Net sales									15,912	18,165	23,925
Germany | Elastomeric Material Solutions
Disaggregation of Revenue [Line Items]
Net sales									13,702	9,907	9,211
Germany | Power Electronics Solutions
Disaggregation of Revenue [Line Items]
Net sales									57,761	62,359	54,813
Germany | Other
Disaggregation of Revenue [Line Items]
Net sales									573	584	657
Other EMEA
Disaggregation of Revenue [Line Items]
Net sales									97,989	104,515	93,565
Other EMEA | Advanced Connectivity Solutions
Disaggregation of Revenue [Line Items]
Net sales									19,995	20,591	18,802
Other EMEA | Elastomeric Material Solutions
Disaggregation of Revenue [Line Items]
Net sales									26,720	22,896	22,961
Other EMEA | Power Electronics Solutions
Disaggregation of Revenue [Line Items]
Net sales									44,743	54,528	44,576
Other EMEA | Other
Disaggregation of Revenue [Line Items]
Net sales									6,531	6,500	7,226
Total EMEA
Disaggregation of Revenue [Line Items]
Net sales									185,937	195,530	182,171
Total EMEA | Advanced Connectivity Solutions
Disaggregation of Revenue [Line Items]
Net sales									35,907	38,756	42,727
Total EMEA | Elastomeric Material Solutions
Disaggregation of Revenue [Line Items]
Net sales									40,422	32,803	32,172
Total EMEA | Power Electronics Solutions
Disaggregation of Revenue [Line Items]
Net sales									102,504	116,887	99,389
Total EMEA | Other
Disaggregation of Revenue [Line Items]
Net sales									$ 7,104	$ 7,084	$ 7,883