Earnings (Loss) Per Share (Tables)

6 Months Ended

Mar. 31, 2024

Earnings Per Share [Abstract]

Computation of basic and diluted (loss) earnings per share

	Three Months Ended March 31,				Six Months Ended March 31,
	2024		2023		2024		2023
Net earnings	$	97.2	$	54.1	$	185.3	$	146.0
Impact of redeemable NCI	—		3.4		—		9.1
Net earnings for basic earnings per share	$	97.2	$	57.5	$	185.3	$	155.1
Impact of interest expense, net of tax, related to convertible senior notes	2.7		2.7		5.4		5.4
Net earnings for diluted earnings per share	$	99.9	$	60.2	$	190.7	$	160.5
Weighted-average shares for basic earnings per share	60.8		58.8		60.6		58.8
Effect of dilutive securities:
Stock options	0.3		0.3		0.3		0.4
Stock appreciation rights	—		0.1		—		0.1
Restricted stock units	0.3		0.4		0.4		0.5
Market-based performance restricted stock units	0.8		0.6		0.7		0.5
Earnings-based performance restricted stock units	—		0.1		0.1		0.1
Shares issuable upon conversion of convertible senior notes	5.4		5.4		5.4		5.4
Total dilutive securities	6.8		6.9		6.9		7.0
Weighted-average shares for diluted earnings per share	67.6		65.7		67.5		65.8
Earnings per Common Share:
Basic	$	1.60	$	0.98	$	3.06	$	2.64
Diluted	$	1.48	$	0.92	$	2.83	$	2.44

Antidilutive Securities Excluded from Computation of Diluted (Loss) Earnings Per Share

	Three Months Ended March 31,		Six Months Ended March 31,
	2024	2023	2024	2023
Restricted stock units	—	—	—	0.1
Market-based performance restricted stock units	—	0.2	—	0.2