Earnings Per Share - Schedule of Earnings Per Share, Basic and Dilutive (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Numerator:
Income from continuing operations	$ 220,718	$ 122,180	$ 53,316
Loss from discontinued operations, net of tax	(14)	(159)	(1,090)
Net income	$ 220,704	$ 122,021	$ 52,226
Denominator:
Basic weighted-average shares (in shares)	30,432	29,954	29,704
Dilutive effect of restricted stock awards (in shares)	357	461	229
Dilutive effect of stock options (in shares)	7	22	15
Diluted weighted-average shares (in shares)	30,796	30,437	29,948
Basic income (loss) per share:
Continuing operations (in dollars per share)	$ 7.25	$ 4.08	$ 1.80
Discontinued operations (in dollars per share)	0	(0.01)	(0.04)
Total (in dollars per share)	7.25	4.07	1.76
Diluted income (loss) per share:
Continuing operations (in dollars per share)	7.17	4.01	1.78
Discontinued operations (in dollars per share)	0	0	(0.04)
Total (in dollars per share)	$ 7.17	$ 4.01	$ 1.74