Common Stock and Stock Compensation - Schedule of Restricted Stock Award Activity (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2022
Restricted stock
Shares
Outstanding, beginning balance (in shares)	2,555,899
Granted (in shares)	1,442,461
Released (in shares)	(1,235,235)
Cancelled (in shares)	(63,211)
Outstanding, ending balance (in shares)	2,699,914	2,555,899
Weighted Average Grant Date Fair Value
Outstanding, beginning balance (in dollars per share)share)	$ 6.80
Granted (in dollars per share)	7.59	$ 7.82	$ 7.24
Released (in dollars per share)	5.28
Cancelled (in dollars per share)	7.32
Outstanding, ending balance (in dollars per share)	$ 7.91	6.80
Performance adjustment (in shares)	353,993
Number of shares withheld to satisfy related federal income tax withholding (in shares)	380,931
Weighted average grant-date fair value per share granted (in dollars per share)	$ 7.59	$ 7.82	$ 7.24
Restricted Stock and Phantom Share-Based Awards
Weighted Average Grant Date Fair Value
Total market value of shares released	$ 10.7	$ 4.7	$ 3.7