Restructuring and Impairment Charges (Restructuring and Impairment Charges) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Restructuring and Impairment
Total Restructuring and Impairment Charges	$ 4,038	$ 3,567	$ 734
Advanced Connectivity Solutions | Severance and other related costs
Restructuring and Impairment
Total Restructuring and Impairment Charges	244	1,305	375
Advanced Connectivity Solutions | Allocated impairment charges
Restructuring and Impairment
Total Restructuring and Impairment Charges	1,506	161	0
Elastomeric Material Solutions | Severance and other related costs
Restructuring and Impairment
Total Restructuring and Impairment Charges	2,152	834	176
Elastomeric Material Solutions | Allocated impairment charges
Restructuring and Impairment
Total Restructuring and Impairment Charges	0	103	0
Power Electronics Solutions | Severance and other related costs
Restructuring and Impairment
Total Restructuring and Impairment Charges	136	621	183
Power Electronics Solutions | Allocated impairment charges
Restructuring and Impairment
Total Restructuring and Impairment Charges	$ 0	$ 543	$ 0