Derivative Instruments - Schedule of Notional Amounts of Commodity Index (Details) - lb lb in Millions	Mar. 31, 2022	Sep. 30, 2021
Aluminum index contracts
Derivatives, Fair Value [Line Items]
Derivative nonmonetary notional amount (in pounds)	0.0	7.2
Steel index contracts
Derivatives, Fair Value [Line Items]
Derivative nonmonetary notional amount (in pounds)	14.6	0.7

Nominal number of units used to calculate payment on derivative.

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