Fair Value Measurements (Tables)

12 Months Ended

Sep. 30, 2019

Fair Value Disclosures [Abstract]

Financial Assets and Liabilities Measured at Fair Value on a Recurring Basis

The following table presents, on a gross basis, our financial assets and liabilities including both current and noncurrent portions, that are measured at fair value on a recurring basis within the fair value hierarchy as described in Note 2:

	Asset (Liability)
	Level 1			Level 2			Level 3		Total
September 30, 2019:
Derivative instruments:
Assets:
Commodity contracts	$	32.0		$	10.1		$	—	$	42.1
Foreign currency contracts	$	—		$	59.0		$	—	$	59.0
Liabilities:
Commodity contracts	$	(62.3	)	$	(112.7	)	$	—	$	(175.0	)
Foreign currency contracts	$	—		$	(4.3	)	$	—	$	(4.3	)
Interest rate contracts	$	—		$	(12.3	)	$	—	$	(12.3	)
Non-qualified supplemental postretirement grantor trust investments (a)	$	39.7		$	—		$	—	$	39.7
September 30, 2018
Derivative instruments:
Assets:
Commodity contracts	$	93.5		$	117.5		$	—	$	211.0
Foreign currency contracts	$	—		$	20.6		$	—	$	20.6
Cross-currency contracts	$	—		$	0.9		$	—	$	0.9
Liabilities:
Commodity contracts	$	(33.6	)	$	(9.8	)	$	—	$	(43.4	)
Foreign currency contracts	$	—		$	(14.4	)	$	—	$	(14.4	)
Interest rate contracts	$	—		$	(1.0	)	$	—	$	(1.0	)
Non-qualified supplemental postretirement grantor trust investments (a)	$	40.8		$	—		$	—	$	40.8

(a)

Consists primarily of mutual fund investments held in grantor trusts associated with non-qualified supplemental retirement plans (see Note 8).

Schedule of Carrying Amount and Estimated Fair Value of Long-term Debt

The carrying amount and estimated fair value of our long-term debt (including current maturities but excluding unamortized debt issuance costs) were as follows:

	2019		2018
Carrying amount	$	5,856.6	$	4,199.4
Estimated fair value	$	6,189.3	$	4,150.3