Earnings (Loss) Per Share of Common Stock - Reconciliation of Numerator and Denominator for Basic and Diluted (Loss) Earnings Per Share Calculation (Details) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended		9 Months Ended
		Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Earnings Per Share [Abstract]
Net Income (Loss)		$ 6.1	$ 32.3	$ (7.4)	$ 28.3
Less: Dividends on Series A convertible preferred shares		(8.9)	(8.9)	(26.8)	(26.8)
Less: Earnings allocated to Convertible Preferred Shares		0.0	(8.5)	0.0	(0.5)
Net (loss) income available to common shareholders		$ (2.8)	$ 14.9	$ (34.2)	$ 1.0
Weighted average number of common shares outstanding – basic		93,092,000	95,228,000	93,918,000	95,302,000
Basic (loss) income per share		$ (0.03)	$ 0.16	$ (0.36)	$ 0.01
Net (loss) income available to common shareholders - diluted		$ (2.8)	$ 14.9	$ (34.2)	$ 1.0
Stock compensation awards		0	2,516,000	0	839,000
Weighted average number of common shares outstanding - diluted		93,092,000	97,744,000	93,918,000	96,141,000
Diluted (loss) income per share		$ (0.03)	$ 0.15	$ (0.36)	$ 0.01
Weighted average number of anti-dilutive Series A convertible preferred shares, options and restricted stock(a)	[1]	58,599,000	54,921,000	58,736,000	58,045,000

[1] Weighted average number of anti-dilutive options is based upon the average closing price of the Company’s common stock on the NYSE for the period.