Commitments and Contingencies (Pace, Piedmont, Pasadena - Narrative) (Details) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2020 USD ($)	Sep. 30, 2012 USD ($) surfaceImpoundmentUnit	Sep. 30, 2006 USD ($)	Mar. 31, 2024 USD ($)	Sep. 30, 2023 USD ($)
Environmental
Loss Contingencies [Line Items]
Accrual for environmental loss contingencies				$ 62.2	$ 64.5
Accrual for environmental loss contingencies, maximum payout period				26 years
Pace, Florida
Loss Contingencies [Line Items]
Accrual for environmental loss contingencies			$ 42.0	$ 36.3
Change in estimated exposure	$ 19.0
Pace, Florida | Discontinued operations
Loss Contingencies [Line Items]
Pretax environmental expense	$ 19.0		$ 42.0
Pasadena, Texas
Loss Contingencies [Line Items]
Accrual for environmental loss contingencies				$ 10.4
Number of closed facilities | surfaceImpoundmentUnit		2
Total anticipated exposure		$ 13.0