Business Segment Information (Schedule Of Capital Expenditures) (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2016
Capital Expenditures	$ 20,589	$ 29,728	$ 13,843
Filtration [Member]
Capital Expenditures	7,000	10,200	3,300
Test [Member]
Capital Expenditures	3,000	4,500	3,300
USG [Member]
Capital Expenditures	5,200	7,600	3,300
Technical Packaging [Member]
Capital Expenditures	5,400	7,400	3,900
Corporate [Member]
Capital Expenditures	$ 0	$ 0	$ 0