The amount of annual revenue increase from new rates.

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- Definition

Public Utilities, Approved Rate Increase (Decrease), Annualized Revenue

+ References

No definition available.

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- Definition

Amount of public utility's approved rate increase (decrease) by regulatory agency.

+ References

No definition available.

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- Definition

Amount of public utility's requested rate increase (decrease) with regulatory agency.

+ References

No definition available.

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Remaining recovery period of regulatory assets for which no return on investment during recovery period is provided, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 980
-SubTopic 340
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478742/980-340-50-1

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 980
-SubTopic 340
-Section 55
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478098/980-340-55-2

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Note 5 - Regulatory Matters (Details Textual) - USD ($) $ in Thousands										15 Months Ended
	Apr. 16, 2024	Jan. 01, 2024	Dec. 14, 2023	Dec. 13, 2023	Oct. 04, 2023	Apr. 30, 2023	Apr. 20, 2023	Jan. 01, 2023	Dec. 26, 2022	Apr. 16, 2024	Mar. 31, 2024
Spire Missouri [Member] \| Missouri Public Service Commission [Member] \| Infrastructure System Replacement Surcharge [Member]
Public Utilities, Requested Rate Increase (Decrease), Amount									$ 0	$ 36,900
Public Utilities, Approved Rate Increase (Decrease), Amount					$ 12,400		$ 7,700
Spire Missouri [Member] \| Missouri Public Service Commission [Member] \| Infrastructure System Replacement Surcharge [Member] \| Subsequent Event [Member]
Public Utilities, Requested Rate Increase (Decrease), Amount	$ 16,800
Spire Alabama Inc [Member] \| Alabama Public Service Commission [Member]
Annual Revenue Increase From Rates, Amount		$ 14,300						$ 15,000
Spire Gulf [Member]
Annual Revenue Increase From Rates, Amount				$ 2,700
Public Utilities, Approved Rate, Increase Decrease Annualized Revenue				$ 2,000		$ 1,800		2,500
Spire Mississippi [Member]
Public Utilities, Approved Rate, Increase Decrease Annualized Revenue			$ 800					$ 800
Future Income Taxes Due From Customers and Pension and Other Postretirement Benefit Costs [Member]
Remaining Recovery Period of Regulatory Assets for which No Return on Investment During Recovery Period is Provided (Year)											20 years
PGA Assets [Member]
Remaining Recovery Period of Regulatory Assets for which No Return on Investment During Recovery Period is Provided (Year)											2 years
PGA Assets Not Earning A Return [Member]
Remaining Recovery Period of Regulatory Assets for which No Return on Investment During Recovery Period is Provided (Year)											15 years