Income Taxes (Summary of Changes in Valuation Allowances for Deferred Tax Assets) (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019
Deferred Tax Assets [Abstract]
Balance at Beginning of Year	$ 63,205	$ 0	$ 5,000
Additions	0	63,205	0
Deductions	5,560	0	5,000
Balance at End of Year	$ 57,645	$ 63,205	$ 0