Derivatives (Tables)

6 Months Ended

Mar. 31, 2023

Derivative Instruments and Hedging Activities Disclosure [Abstract]

Summary Of Outstanding Notional Amounts

The following table sets forth the outstanding notional amounts related to our derivative instruments (in millions):

	Metric	March 31, 2023		September 30, 2022
Designated cash flow hedges:
Natural gas commodity contracts	MMBtu		21.3		18.3
Undesignated derivatives:
Foreign currency contracts (1)	Mexican pesos		—		8,000.0

At September 30, 2022, the outstanding foreign currency exchange contract was related to the purchase of 8.0 billion Mexican pesos ($389.9 million) for refinancing Grupo Gondi's external debt upon the Grupo Gondi Acquisition on December 1, 2022.

Summary of Location and Fair Values of Derivative Instruments

The following table sets forth the location and fair values of our derivative instruments (in millions):

	Consolidated Balance  Sheet Caption	March 31, 2023		September 30, 2022
Designated cash flow hedges:
Natural gas commodity contracts	Other current liabilities (1)	$	32.3	$	12.0
Undesignated derivatives:
Foreign currency contracts	Other current assets	$	—	$	3.4

(1)At September 30, 2022, liability positions by counterparty were partially offset by $2.3 million of asset positions where we had an enforceable right of netting.

Summary of Gains (Losses) Recognized in Accumulated Other Comprehensive Loss, Net of Tax for Cash Flow Hedges

The following table sets forth gains (losses) recognized in accumulated other comprehensive loss, net of tax for cash flow hedges (in millions):

	Three Months Ended					Six Months Ended
	March 31,					March 31,
	2023			2022		2023			2022
Natural gas commodity contracts	$	(3.4	)	$	—	$	(15.3	)	$	—

Summary of Gains (Losses) Recognized in the Statements of Income

The following table sets forth amounts of gains (losses) recognized in the consolidated statements of operations for cash flow hedges reclassified from accumulated other comprehensive loss (in millions):

		Three Months Ended					Six Months Ended
		March 31,					March 31,
	Consolidated Statement  of Operations Caption	2023			2022		2023			2022
Natural gas commodity contracts	Cost of goods sold	$	(26.8	)	$	—	$	(40.0	)	$	—

The following table sets forth amounts of gains (losses) recognized in the consolidated statements of operations for derivatives not designated as hedges (in millions):

		Three Months Ended				Six Months Ended
		March 31,				March 31,
	Consolidated Statement  of Operations Caption	2023		2022		2023		2022
Foreign currency contracts	Other (expense) income, net	$	—	$	—	$	19.7	$	—