Operating Segments and Related Information (Details 2) - 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
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue	$ 524,337	$ 466,414	$ 482,015	$ 450,923	$ 489,044	$ 471,248	$ 481,998	$ 444,736	$ 1,923,689	$ 1,887,026	$ 1,775,686
Intersegment revenue									0	0	0
Earnings (loss) from operations									317,242	273,260	318,606
Industrial
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue									1,156,058	1,092,085	1,112,250
Intersegment revenue									12,206	15,073	19,052
Earnings (loss) from operations									344,376	276,167	268,472
Government and defense
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue									767,631	794,941	663,436
Intersegment revenue									7,580	5,507	11,409
Earnings (loss) from operations									168,469	196,592	194,009
Total Segments [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue										1,887,026
Earnings (loss) from operations									512,845	472,759	462,481
Corporate and Other [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Intersegment revenue									$ 19,786	$ 20,580	$ 30,461