Operating Segments and Related Information (Details 2) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Business Unit Reporting, Revenue Reconciling Item [Line Items]
Revenue	$ 466,414	$ 471,248	$ 1,399,352	$ 1,397,982
Earnings from operations	86,577	74,388	214,882	219,207
Defense Technologies
Business Unit Reporting, Revenue Reconciling Item [Line Items]
Revenue	185,295	213,348	541,620	584,207
Intersegment revenue	(2,289)	(959)	(5,562)	(3,906)
Earnings from operations	38,811	53,809	113,120	146,485
Industrial Technologies
Business Unit Reporting, Revenue Reconciling Item [Line Items]
Revenue	281,119	257,900	857,732	813,775
Intersegment revenue	(3,639)	(3,759)	(10,269)	(12,221)
Earnings from operations	87,743	63,713	259,145	204,365
Eliminations
Business Unit Reporting, Revenue Reconciling Item [Line Items]
Intersegment revenue	(5,928)	(4,718)	(15,831)	(16,127)
Total Segments [Member]
Business Unit Reporting, Revenue Reconciling Item [Line Items]
Revenue	466,414	471,248	1,399,352	1,397,982
Intersegment revenue	0	0	0	0
Earnings from operations	$ 126,554	$ 117,522	$ 372,265	$ 350,850