Business Realignment and Restructuring (Schedule of Restructuring and Related Costs) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Particulate Matter Product Line Strategic Exit [Member]
Restructuring Cost and Reserve [Line Items]
Charge to expense			$ 2,894
Cash payments			(70)
Utilization, Non-Cash			(2,824)
Canton Facility Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve, Beginning Balance			2,636
Charge to expense			2,881	$ 9,275
Cash payments			(5,308)	(3,679)
Restructuring Reserve, Ending Balance	$ 209	$ 5,596	209	5,596
Control Devices [Member] | Particulate Matter Product Line Strategic Exit [Member]
Restructuring Cost and Reserve [Line Items]
Charge to expense	342		2,894
Control Devices [Member] | Canton Facility Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Charge to expense	197	3,607	2,881	9,275
Control Devices [Member] | Cost of Goods Sold [Member] | Particulate Matter Product Line Strategic Exit [Member]
Restructuring Cost and Reserve [Line Items]
Charge to expense	340		503
Control Devices [Member] | Cost of Goods Sold [Member] | Canton Facility Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Charge to expense		2,567	1,659	6,173
Control Devices [Member] | Selling, General and Administrative Expenses [Member] | Particulate Matter Product Line Strategic Exit [Member]
Restructuring Cost and Reserve [Line Items]
Charge to expense	2		2,391
Control Devices [Member] | Selling, General and Administrative Expenses [Member] | Canton Facility Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Charge to expense		287	549	762
Control Devices [Member] | Design and Development Expense [Member] | Canton Facility Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Charge to expense		753	673	2,340
Electronics [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve, Beginning Balance			52	656
Charge to expense	567	157	2,195	469
Cash payments			(1,977)	(788)
Utilization, Non-Cash				(286)
Restructuring Reserve, Ending Balance	270	51	270	51
Electronics [Member] | Cost of Goods Sold [Member]
Restructuring Cost and Reserve [Line Items]
Charge to expense	132		132
Electronics [Member] | Selling, General and Administrative Expenses [Member]
Restructuring Cost and Reserve [Line Items]
Charge to expense	383		1,634
Electronics [Member] | Design and Development Expense [Member]
Restructuring Cost and Reserve [Line Items]
Charge to expense	52		429
Employee Termination [Member] | Canton Facility Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve, Beginning Balance			2,636
Charge to expense			1,119	6,967
Cash payments			(3,546)	(1,371)
Restructuring Reserve, Ending Balance	209	5,596	209	5,596
Employee Termination [Member] | Electronics [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve, Beginning Balance			52	520
Charge to expense			961	(30)
Cash payments			(743)	(442)
Utilization, non-cash				3
Restructuring Reserve, Ending Balance	$ 270	$ 51	270	51
Non-Cash Fixed Asset Charges [Member] | Particulate Matter Product Line Strategic Exit [Member]
Restructuring Cost and Reserve [Line Items]
Charge to expense			2,824
Utilization, Non-Cash			(2,824)
Accelerated Depreciation [Member] | Electronics [Member]
Restructuring Cost and Reserve [Line Items]
Charge to expense				289
Utilization, Non-Cash				(289)
Contract Termination [Member] | Electronics [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve, Beginning Balance				17
Charge to expense			452	24
Cash payments			(452)	(41)
Other Restructuring [Member] | Particulate Matter Product Line Strategic Exit [Member]
Restructuring Cost and Reserve [Line Items]
Charge to expense			70
Cash payments			(70)
Other Restructuring [Member] | Canton Facility Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Charge to expense			1,762	2,308
Cash payments			(1,762)	(2,308)
Other Restructuring [Member] | Electronics [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve, Beginning Balance				119
Charge to expense			782	186
Cash payments			$ (782)	$ (305)