(Loss) Earnings Per Share of Common Stock - Reconciliation of Numerator and Denominator for Basic and Diluted Earnings (loss) Per Share Calculation (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions		3 Months Ended		6 Months Ended
		Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2023	Mar. 31, 2022
Earnings Per Share [Abstract]
Net (loss) income available to common stockholders		$ (22.0)	$ 0.7	$ (40.9)	$ (12.1)
Weighted average number of common shares outstanding - basic		93,475,000	100,282,000	93,362,000	102,705,000
Basic (loss) earnings per share		$ (0.23)	$ 0.01	$ (0.44)	$ (0.12)
Weighted average number of common shares outstanding – diluted		93,475,000	100,608,000	93,362,000	102,705,000
Diluted (loss) earnings per share		$ (0.23)	$ 0.01	$ (0.44)	$ (0.12)
Weighted average number of anti-dilutive options and restricted stock	[1]	5,320,000	4,005,787	5,321,000	5,363,000

[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