Earnings Per Share (Reconciliation of Net Earnings to Net Earnings Per Share Basic and Diluted) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2022
Numerator:
Net earnings	$ 372,971	$ 232,368	$ 171,698
Denominator:
Basic shares outstanding	60,076	59,908	61,517
Dilutive effect of stock options; restricted and performance stock units	2,008	1,574	1,737
Diluted shares outstanding	62,084	61,482	63,254
Income per common share:
Basic earnings per share	$ 6.21	$ 3.88	$ 2.79
Diluted earnings per share	$ 6.01	$ 3.78	$ 2.71