Earnings Per Share - Schedule of Earnings Per Share, Basic and Dilutive (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Earnings Per Share [Abstract]
Income (loss) from continuing operations	$ 24,627	$ 15,270	$ 10,615	$ 2,804	$ 2,464	$ 11,625	$ (100,832)	$ 7,322	$ 53,316	$ (79,421)	$ (45,046)
Loss from discontinued operations, net of tax									(1,090)	(99)	(329)
Net income (loss)									$ 52,226	$ (79,520)	$ (45,375)
Basic weighted-average shares (in shares)									29,704	30,617	32,141
Dilutive effect of restricted stock awards (in shares)									229	0	0
Dilutive effect of stock options (in shares)									15	0	0
Diluted weighted-average shares (in shares)									29,948	30,617	32,141
Basic income (loss) per share:
Continuing operations (in dollars per share)	$ 0.83	$ 0.51	$ 0.36	$ 0.09	$ 0.08	$ 0.38	$ (3.28)	$ 0.23	$ 1.80	$ (2.59)	$ (1.40)
Discontinued operations (in dollars per share)									(0.04)	(0.01)	(0.01)
Total (in dollars per share)									1.76	(2.60)	(1.41)
Diluted income (loss) per share:
Continuing operations (in dollars per share)	$ 0.82	$ 0.51	$ 0.35	$ 0.09	$ 0.08	$ 0.38	$ (3.28)	$ 0.23	1.78	(2.59)	(1.40)
Discontinued operations (in dollars per share)									(0.04)	(0.01)	(0.01)
Total (in dollars per share)									$ 1.74	$ (2.60)	$ (1.41)