Earnings Per Share - Schedule of Earnings Per Share. Basic and Dilutive (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:
Income from continuing operations, net of tax	$ 37,142	$ 15,270	$ 73,821	$ 28,689
Loss from discontinued operations, net of tax	(7)	(82)	(161)	(141)
Net income	$ 37,135	$ 15,188	$ 73,660	$ 28,548
Denominator:
Basic weighted-average shares (in shares)	30,022	29,597	29,915	29,738
Dilutive effect of restricted stock awards (in shares)	517	76	352	267
Dilutive effect of stock options (in shares)	23	1	25	9
Dilutive weighted-average shares (in shares)	30,562	29,674	30,292	30,014
Basic income (loss) per share:
Continuing Operations (in USD per share)	$ 1.24	$ 0.51	$ 2.47	$ 0.96
Discontinued operations (in USD per share)	0	0	(0.01)	0
Total (in USD per share)	1.24	0.51	2.46	0.96
Diluted income (loss) per share:
Continuing operations (in USD per share)	1.22	0.51	2.44	0.95
Discontinued operations (in USD per share)	0	0	(0.01)	0
Total (in USD per share)	$ 1.22	$ 0.51	$ 2.43	$ 0.95