Income Tax Expense - Principal Components Of Income Tax Expense (Benefit) From Continuing Operations (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Income Tax Expense
Federal, Current	$ 10,982	$ 13,888	$ 7,663
Federal, Deferred	1,507	250	(22,329)
State and local, Current	2,042	3,039	1,885
State and local, Deferred	(905)	98	2,899
Foreign, Current	2,875	2,439	2,208
Foreign, Deferred	(2,223)	674	2,504
Income Tax Expense (Benefit), Total	$ 14,278	$ 20,388	$ (5,170)