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	3 Months Ended		9 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Numerator:
Net earnings	$ 48,861	$ 38,465	$ 158,744	$ 183,156
Denominator:
Basic	63,559	62,309	63,215	62,188
Dilutive effect of stock options and restricted stock	2,351	1,118	2,284	2,085
Diluted shares outstanding	65,910	63,427	65,499	64,273
Income per common share:
Basic earnings per share	$ 0.77	$ 0.62	$ 2.51	$ 2.95
Diluted earnings per share	$ 0.74	$ 0.61	$ 2.42	$ 2.85