Note 7 - Notes Payable and Credit Agreements (Tables)

12 Months Ended

Sep. 30, 2023

Notes Tables

Schedule of Short-Term Debt [Table Text Block]

	Spire			Spire						Spire
	(Parent Only)			Missouri						Alabama			Spire
	CP			Term			Spire			Spire			Consol-
	Program			Loan			Note			Note			idated
Year Ended September 30, 2023
Highest borrowings outstanding	$	1,282.0		$	250.0		$	656.9		$	274.0		$	1,482.0
Lowest borrowings outstanding		354.4			—			3.8			76.7			489.0
Weighted average borrowings		776.3			66.8			327.9			119.1			843.1
Weighted average interest rate		5.0	%		5.5	%		4.9	%		4.9	%		5.0	%
As of September 30, 2023
Borrowings outstanding	$	955.5		$	—		$	540.6		$	124.1		$	955.5
Weighted average interest rate		5.6	%		0.0	%		5.6	%		5.6	%		5.6	%
As of September 30, 2022
Borrowings outstanding	$	1,037.5		$	—		$	445.3		$	260.9		$	1,037.5
Weighted average interest rate		3.3	%		0.0	%		3.3	%		3.3	%		3.3	%