Business Segment Information - Schedule Of Identifiable Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Sep. 30, 2020
Identifiable Assets	$ 1,577,345	$ 1,370,186
A&D
Identifiable Assets	270,000	276,200
USG
Identifiable Assets	197,500	144,800
Test
Identifiable Assets	153,600	153,000
Corporate, Non-Segment [Member]
Other Assets	$ 956,200	$ 796,200