Income Taxes (Components of Income Tax Expense (Benefit)) (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2017
Current:
Federal	$ 40,173	$ 39,979	$ 17,872
State	2,402	3,697	1,379
Foreign	34,660	25,968	15,118
Deferred:
Federal	(2,015)	(10,519)	16,907
State	(2,948)	(3,784)	(2,561)
Foreign	(11,262)	(16,141)	3,525
Income tax expense	$ 61,010	$ 39,200	$ 52,240