Consolidated Statements of Shareholder's Equity - USD ($) shares in Millions, $ in Millions	Total	Open Market Purchases and Private Purchases	Accelerated Share Repurchase	Total Shareholders' Equity	Total Shareholders' Equity Open Market Purchases and Private Purchases	Total Shareholders' Equity Accelerated Share Repurchase	Common Stock	Common Stock Open Market Purchases and Private Purchases	Common Stock Accelerated Share Repurchase	Additional Paid-in Capital	Additional Paid-in Capital Accelerated Share Repurchase	Accumulated Earnings (Deficit)	Accumulated Other Comprehensive Loss	Treasury Stock	Treasury Stock Open Market Purchases and Private Purchases	Treasury Stock Accelerated Share Repurchase	Non- controlling Interest
Balance at beginning of period (in shares) at Sep. 30, 2020							43.1
Balance at beginning of period at Sep. 30, 2020	$ 1,415.8			$ 1,407.5			$ 0.5			$ 2,054.3		$ 243.9	$ (284.7)	$ (606.5)			$ 8.3
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income from continuing operations	15.3			15.1								15.1					0.2
Income (loss) from discontinued operations, net of tax	174.3			174.5								174.5					(0.2)
Other comprehensive income (loss), net of tax	$ 49.8			49.4									49.4				0.4
Treasury stock repurchases (in shares)	(1.6)		0.0				(1.6)
Treasury stock repurchases	$ (125.8)			(125.8)										(125.8)		$ 0.0
Restricted stock issued and related tax withholdings (in shares)							0.3
Restricted stock issued and related tax withholdings	(4.9)			(4.9)						(20.2)		0.0		15.3
Share based compensation	29.7			29.7						29.7
Dividend paid to common shareholders	(73.6)			(73.6)								(73.6)
Dividend paid by subsidiary to NCI	(1.6)																(1.6)
Balance at end of period (in shares) at Sep. 30, 2021							41.8
Balance at end of period at Sep. 30, 2021	1,479.0			1,471.9			$ 0.5			2,063.8		359.9	(235.3)	(717.0)			7.1
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income from continuing operations	(77.0)			(77.2)								(77.2)					0.2
Income (loss) from discontinued operations, net of tax	149.7			148.8								148.8					0.9
Other comprehensive income (loss), net of tax	$ (68.7)			(67.8)									(67.8)				(0.9)
Treasury stock repurchases (in shares)	(1.4)		0.0				(1.4)
Treasury stock repurchases	$ (134.0)			(134.0)										(134.0)		0.0
Restricted stock issued and related tax withholdings (in shares)							0.4
Restricted stock issued and related tax withholdings	(24.5)			(24.5)						(46.7)				22.2
Share based compensation	15.4			15.4						15.4
Dividend paid to common shareholders	(69.4)			(69.4)								(69.4)
Dividend paid by subsidiary to NCI	(1.4)																(1.4)
Balance at end of period (in shares) at Sep. 30, 2022							40.8
Balance at end of period at Sep. 30, 2022	1,269.1			1,263.2			$ 0.5			2,032.5		362.1	(303.1)	(828.8)			5.9
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income from continuing operations	(233.7)			(233.8)								(233.8)					0.1
Income (loss) from discontinued operations, net of tax	2,035.6			2,035.3								2,035.3					0.3
Sale and deconsolidation of assets held for sale	19.4			25.3									25.3				(5.9)
Other comprehensive income (loss), net of tax	$ 28.7			28.4									28.4				0.3
Treasury stock repurchases (in shares)	(5.7)		(5.3)					(0.4)	(5.3)
Treasury stock repurchases		$ (38.9)	$ (500.0)		$ (38.9)	$ (500.0)					$ (100.0)			(434.7)	$ (38.9)	$ (400.0)
Restricted stock issued and related tax withholdings (in shares)							0.2
Restricted stock issued and related tax withholdings	$ (12.9)			(12.9)						(30.3)				17.4
Share based compensation	18.6			18.6						18.6
Dividend paid to common shareholders	(67.6)			(67.6)								(67.6)
Balance at end of period (in shares) at Sep. 30, 2023							35.3
Balance at end of period at Sep. 30, 2023	$ 2,518.3			$ 2,517.6			$ 0.5			$ 1,920.8		$ 2,096.0	$ (249.4)	$ (1,250.3)			$ 0.7