Note 7 - Fair Value Measurement (Tables)

3 Months Ended

Dec. 31, 2022

Notes Tables

Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]

	Quoted Prices in Active Markets (Level 1)		Significant Observable Inputs (Level 2)		Effects of Netting and Cash Margin Receivables /Payables			Total
As of December 31, 2022
ASSETS
Gas Utility:
U.S. stock/bond mutual funds	$	19.5	$	—	$	—		$	19.5
NYMEX/ICE natural gas contracts		0.4		—		(0.4	)		—
Gasoline and heating oil contracts		0.2		—		(0.2	)		—
Gas Marketing:
NYMEX/ICE natural gas contracts		52.0		—		(52.0	)		—
Natural gas commodity contracts		92.9		—		(13.2	)		79.7
Other:
U.S. stock/bond mutual funds		28.3		—		—			28.3
Interest rate swaps		61.4		—		—			61.4
Total	$	254.7	$	—	$	(65.8	)	$	188.9
LIABILITIES
Gas Utility:
NYMEX/ICE natural gas contracts	$	35.7	$	—	$	(35.7	)	$	—
Gasoline and heating oil contracts		0.2		—		(0.2	)		—
Gas Marketing:
NYMEX/ICE natural gas contracts		58.4		—		(58.4	)		—
Natural gas commodity contracts		71.1		—		(13.2	)		57.9
Other:
Interest rate swaps		0.8		—		—			0.8
Total	$	166.2	$	—	$	(107.5	)	$	58.7

	Quoted Prices in Active Markets (Level 1)		Significant Observable Inputs (Level 2)		Effects of Netting and Cash Margin Receivables /Payables			Total
As of September 30, 2022
ASSETS
Gas Utility:
U.S. stock/bond mutual funds	$	19.1	$	—	$	—		$	19.1
NYMEX/ICE natural gas contracts		57.8		—		(57.8	)		—
Gas Marketing:
NYMEX/ICE natural gas contracts		91.8		—		(91.8	)		—
Natural gas commodity contracts		56.6		—		(4.0	)		52.6
Other:
U.S. stock/bond mutual funds		29.3		—		—			29.3
Interest rate swaps		63.6		—		—			63.6
Total	$	318.2	$	—	$	(153.6	)	$	164.6
LIABILITIES
Gas Utility:
NYMEX/ICE natural gas contracts	$	30.7	$	—	$	(30.7	)	$	—
Gas Marketing:
NYMEX/ICE natural gas contracts		82.3		—		(82.3	)		—
Natural gas commodity contracts		65.5		—		(4.0	)		61.5
Total	$	178.5	$	—	$	(117.0	)	$	61.5
As of December 31, 2021
ASSETS
Gas Utility:
U.S. stock/bond mutual funds	$	24.8	$	—	$	—		$	24.8
NYMEX/ICE natural gas contracts		2.4		—		(2.4	)		—
Gas Marketing:
NYMEX/ICE natural gas contracts		—		67.0		(67.0	)		—
Natural gas commodity contracts		—		40.4		(2.3	)		38.1
Other:
U.S. stock/bond mutual funds		24.6		—		—			24.6
Interest rate swaps		9.4		—		(5.6	)		3.8
Total	$	61.2	$	107.4	$	(77.3	)	$	91.3
LIABILITIES
Gas Utility:
NYMEX/ICE natural gas contracts	$	8.6	$	—	$	(8.6	)	$	—
Gas Marketing:
NYMEX/ICE natural gas contracts		—		40.2		(40.2	)		—
Natural gas commodity contracts		—		77.9		(2.3	)		75.6
Other:
Interest rate swaps		7.3		—		(5.6	)		1.7
Total	$	15.9	$	118.1	$	(56.7	)	$	77.3

	Quoted Prices in Active Markets (Level 1)		Significant Observable Inputs (Level 2)		Effects of Netting and Cash Margin Receivables /Payables			Total
As of December 31, 2022
ASSETS
U.S. stock/bond mutual funds	$	19.5	$	—	$	—		$	19.5
NYMEX/ICE natural gas contracts		0.4		—		(0.4	)		—
Gasoline and heating oil contracts		0.2		—		(0.2	)		—
Total	$	20.1	$	—	$	(0.6	)	$	19.5
LIABILITIES
NYMEX/ICE natural gas contracts	$	35.7	$	—	$	(35.7	)	$	—
Gasoline and heating oil contracts		0.2		—		(0.2	)		—
Total	$	35.9	$	—	$	(35.9	)	$	—
As of September 30, 2022
ASSETS
U.S. stock/bond mutual funds	$	19.1	$	—	$	—		$	19.1
NYMEX/ICE natural gas contracts		57.8		—		(57.8	)		—
Total	$	76.9	$	—	$	(57.8	)	$	19.1
LIABILITIES
NYMEX/ICE natural gas contracts	$	30.7	$	—	$	(30.7	)	$	—
As of December 31, 2021
ASSETS
U.S. stock/bond mutual funds	$	24.8	$	—	$	—		$	24.8
NYMEX/ICE natural gas contracts		2.4		—		(2.4	)		—
Total	$	27.2	$	—	$	(2.4	)	$	24.8
LIABILITIES
NYMEX/ICE natural gas contracts	$	8.6	$	—	$	(8.6	)	$	—