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Commitments and Contingencies (Details)			3 Months Ended	9 Months Ended
Commitments and Contingencies (Details)	Jul. 07, 2021 USD ($)	Sep. 20, 2018 subclass	Jul. 31, 2021 USD ($)	Jul. 31, 2021 USD ($)
Loss Contingencies [Line Items]
Standby letters of credit			$ 148,800,000	$ 148,800,000
Surety bonds			679,800,000	679,800,000
Bucio
Loss Contingencies [Line Items]
Loss contingency, number of certified subclasses \| subclass		4
Energy Savings Contracts
Loss Contingencies [Line Items]
Guarantee obligation			238,000,000	238,000,000
Minimum
Loss Contingencies [Line Items]
Amount of reasonably possible loss			0	0
Maximum
Loss Contingencies [Line Items]
Amount of reasonably possible loss			6,000,000	6,000,000
Pending Litigation
Loss Contingencies [Line Items]
Loss contingency accrual			14,400,000	14,400,000
Settled Litigation \| Bucio
Loss Contingencies [Line Items]
Loss contingency accrual			142,900,000	142,900,000
Settlement amount	$ 140,000,000
Settlement reserve			112,900,000	142,900,000
Settled Litigation \| Bucio \| Other Current Liabilities
Loss Contingencies [Line Items]
Loss contingency accrual			$ 2,900,000	$ 2,900,000