Commitments and Contingencies (Litigation and Environmental Narrative) (Details) R$ in Millions	1 Months Ended	12 Months Ended
	Sep. 30, 2010 BRL (R$)	Sep. 30, 2024 USD ($)	Sep. 30, 2024 BRL (R$) site	Sep. 30, 2024 USD ($) site	Sep. 30, 2023 USD ($)
Loss Contingencies [Line Items]
Environmental Loss Contingency, Statement of Financial Position [Extensible Enumeration]			Other noncurrent liabilities	Other noncurrent liabilities	Other noncurrent liabilities
Disputed energy management charges
Loss Contingencies [Line Items]
Gain from Litigation Settlement		$ 7,700,000
Alleged Anticompete Litigation
Loss Contingencies [Line Items]
Civil fines imposed	R$ 179.2	33,000,000
Provision for litigation		$ 0
Maximum of loss contingency range subject to interest			R$ 179.2	$ 33,000,000
Environmental
Loss Contingencies [Line Items]
Approximate number of sites on which settlement has not been reached | site			26	26
Accrual for environmental loss contingencies				$ 79,100,000	$ 64,500,000
Accrual for environmental loss contingencies, maximum payout period			30 years	30 years
Site contingency, cost review, period			5 years	5 years
Environmental | Minimum
Loss Contingencies [Line Items]
Estimate of possible exposure from environment loss contingencies				$ 79,000,000
Environmental | Maximum
Loss Contingencies [Line Items]
Estimate of possible exposure from environment loss contingencies				$ 92,000,000