Summary of Significant Accounting Policies (Earnings Per Share Basic And Diluted) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Accounting Policies [Abstract]
Net income	$ 313,081	$ 476,923	$ 130,695
Weighted average shares outstanding	117,194	116,836	115,663
Dilutive effect of employee stock options, restricted shares and restricted stock units	1,039	1,531	604
Diluted weighted average shares outstanding	118,233	118,367	116,267
Earnings per share-Basic	$ 2.67	$ 4.08	$ 1.13
Earnings per share-Diluted	$ 2.65	$ 4.03	$ 1.12