Business Segment Information (Schedule Of Capital Expenditures) (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2013
Capital Expenditures	$ 12,444	$ 12,714	$ 13,862
Filtration [Member]
Capital Expenditures	6,000	7,000	6,600
Test [Member]
Capital Expenditures	3,100	1,400	3,200
USG [Member]
Capital Expenditures	3,300	4,100	3,900
Corporate [Member]
Capital Expenditures	$ 0	$ 200	$ 200