Earnings Per Share - Schedule of Earnings Per Share. Basic and Dilutive (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Mar. 31, 2022	Mar. 31, 2021
Numerator:
Income from continuing operations	$ 44,678	$ 24,643	$ 79,573	$ 36,679
Loss from discontinued operations, net of tax	(6)	(115)	(16)	(154)
Net income	$ 44,672	$ 24,528	$ 79,557	$ 36,525
Denominator:
Basic weighted-average shares (in shares)	30,594	29,953	30,464	29,862
Dilutive effect of restricted stock awards (in shares)	222	231	300	262
Dilutive effect of stock options (in shares)	7	31	8	26
Dilutive weighted-average shares (in shares)	30,823	30,215	30,772	30,150
Basic income (loss) per share:
Continuing operations (in USD per share)	$ 1.46	$ 0.82	$ 2.61	$ 1.23
Discontinued operations (in USD per share)	0	0	0	(0.01)
Total (in USD per share)	1.46	0.82	2.61	1.22
Diluted income (loss) per share:
Continuing operations (in USD per share)	1.45	0.81	2.59	1.22
Discontinued operations (in USD per share)	0	0	0	(0.01)
Total (in USD per share)	$ 1.45	$ 0.81	$ 2.59	$ 1.21