Public utilities approved rate increase decrease costs from buildings sold excluded from rate base.

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- Definition

Public utilities approved rate increase decrease in regulatory assets excluded from rate base.

+ References

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- Definition

Public Utilities, Approved Rate Increase (Decrease), Rate Case Expenses Excluded From Rate Base

+ References

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- Definition

Remaining Recovery Period of Certain Regulatory Assets for which No Return on Investment During Recovery Period is Provided

+ References

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- Definition

Revenue related to investments.

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- Definition

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

+ References

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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

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

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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

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-Publisher FASB
-Name Accounting Standards Codification
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Regulatory Matters - Additional Information (Details) - USD ($) $ in Millions					3 Months Ended	7 Months Ended
	Jan. 14, 2019	Nov. 30, 2018	Sep. 28, 2018	Apr. 25, 2018	Dec. 31, 2018	Jan. 31, 2019
Public Utilities, General Disclosures [Line Items]
Remaining recovery period for certain regulatory assets for which no return on investment during recovery period is provided (in years)					20 years
Remaining recovery period for regulatory assets for which no return on investment during recovery period is provided (in years)					15 years
Spire Missouri
Public Utilities, General Disclosures [Line Items]
Public utilities, requested rate increase (decrease), amount					$ 1.7
Public utilities, requested rate increase (decrease), percentage					51.00%
Spire Alabama
Public Utilities, General Disclosures [Line Items]
Approved rate increase (decrease) amount					$ (4.1)
Public utilities, requested rate increase (decrease), amount		$ 8.7
Infrastructure System Replacement Surcharge \| Spire Missouri East
Public Utilities, General Disclosures [Line Items]
Approved rate increase (decrease) amount			$ 2.6
Infrastructure System Replacement Surcharge \| Spire Missouri East \| Subsequent Event
Public Utilities, General Disclosures [Line Items]
Applications requests for the approval of revenue related to commission amount						$ 7.4
Infrastructure System Replacement Surcharge \| Spire Missouri West
Public Utilities, General Disclosures [Line Items]
Approved rate increase (decrease) amount			$ 5.4
Infrastructure System Replacement Surcharge \| Spire Missouri West \| Subsequent Event
Public Utilities, General Disclosures [Line Items]
Applications requests for the approval of revenue related to commission amount						$ 8.4
Infrastructure System Replacement Surcharge \| Spire Missouri \| Subsequent Event
Public Utilities, General Disclosures [Line Items]
Public utilities, requested rate increase (decrease), amount	$ 3.2
Infrastructure System Replacement Surcharge \| MoPSC
Public Utilities, General Disclosures [Line Items]
Approved rate increase (decrease), costs from buildings sold in 2014 excluded from rate base				$ 1.8
Rate case expenses				0.9
Pension Cost \| Infrastructure System Replacement Surcharge \| MoPSC
Public Utilities, General Disclosures [Line Items]
Regulatory assets recovery				$ 28.8