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Public Utilities, Maximum Return on Equity, Percentage of Prior Year Revenues

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- Definition

Public Utilities, Rate Increase (Decrease), Index Range, Margin

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- Definition

Regulatory Asset Recovery, Operating and Maintenance Expense, Multiple Extraordinary Events

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- Definition

Regulatory Asset Recovery, Operating and Maintenance Expense, Negative Budget Revenue Variances

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- Definition

Regulatory Asset Recovery, Operating and Maintenance Expense, Self Insurance Policy Limit Amount

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- Definition

Regulatory Asset Recovery, Operating and Maintenance Expense, Single Extraordinary Event

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- Definition

Regulatory Noncurrent Asset, Amortization Period 1

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- Definition

Revenue Subject to Refund, Amortization Period

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Revenue Subject to Refund, Annual Amortization Limit

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- Definition

Revenue Subject to Refund Recognition Period

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- Definition

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

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- Definition

Percentage of public utility's approved return on equity.

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- Definition

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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- Definition

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

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- Definition

Carrying amount as of the balance sheet date of capitalized costs of regulated entities that are not expected to be recovered through revenue sources within one year or the normal operating cycle if longer.

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Remaining balance of regulatory assets for which no return on investment during recovery is provided. In some cases, a regulator may permit an enterprise to include a cost that would be charged to expense by an unregulated enterprise as an allowable cost over a period of time by amortizing that cost for rate-making purposes, but the regulator does not include the unrecovered amount in the rate base.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 980

-SubTopic 340

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6499975&loc=d3e44250-110382

Reference 2: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

-Topic 980

-SubTopic 340

-Section 55

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6591318&loc=d3e44360-110383

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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.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Topic 980

-SubTopic 340

-Section 55

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6591318&loc=d3e44360-110383

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-SubTopic 340

-Section 50

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REGULATORY MATTERS (Details) - USD ($) $ in Millions									12 Months Ended		15 Months Ended
REGULATORY MATTERS (Details) - USD ($) $ in Millions	Dec. 01, 2019	Dec. 01, 2015	Nov. 12, 2015	Aug. 03, 2015	May. 22, 2015	Apr. 17, 2015	Jan. 01, 2014	Dec. 01, 2010	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2013
Public Utilities, General Disclosures [Line Items]
Regulatory assets for which no return on investment during recovery period is provided									$ 372.4	$ 373.9
Remaining recovery period for regulatory assets for which no return on investment during recovery period is provided									15 years
Regulatory assets									$ 737.6	614.3
Laclede Gas
Public Utilities, General Disclosures [Line Items]
Regulatory assets for which no return on investment during recovery period is provided									372.4	373.9
Regulatory assets									573.6	523.7
Alagasco
Public Utilities, General Disclosures [Line Items]
Regulatory assets									$ 163.6	90.6
Potential performance-based adjustment									0.05%
APSC \| Alagasco
Public Utilities, General Disclosures [Line Items]
Approved rate increase									$ 4.9	2.4
Approved return rate on equity							10.80%
Maximum return on equity, percentage of prior year revenues									4.00%
Rate increase (decrease), margin of index range									1.75%
ISRS charges from September 2014 through February 2015 \| MoPSC \| Laclede Gas
Public Utilities, General Disclosures [Line Items]
Requested rate increase						$ 5.5
Approved rate increase					$ 5.4
ISRS charges from September 2014 through February 2015 \| MoPSC \| Missouri Gas Energy (MGE)
Public Utilities, General Disclosures [Line Items]
Requested rate increase						$ 2.9
Approved rate increase					$ 2.8
ISRS charges from March 2014 - August 2014 \| MoPSC \| Laclede Gas
Public Utilities, General Disclosures [Line Items]
Requested rate increase				$ 4.3
ISRS charges from March 2014 - August 2014 \| MoPSC \| Missouri Gas Energy (MGE)
Public Utilities, General Disclosures [Line Items]
Requested rate increase				$ 1.8
Deferred Costs Incurred Prior to YE 1999
Public Utilities, General Disclosures [Line Items]
Regulatory assets										$ 10.5
Regulatory assets amortization period										15 years
Enhanced stability reserve \| APSC \| Alagasco
Public Utilities, General Disclosures [Line Items]
Self insurance policy limit per occurrence									$ 1.0
Revenue subject to refund recognition period								9 years
Subsequent Event \| ISRS charges from March 2014 - August 2014 \| MoPSC \| Laclede Gas
Public Utilities, General Disclosures [Line Items]
Approved rate increase			$ 4.4
Subsequent Event \| ISRS charges from March 2014 - August 2014 \| MoPSC \| Missouri Gas Energy (MGE)
Public Utilities, General Disclosures [Line Items]
Approved rate increase			$ 1.9
Minimum \| APSC \| Alagasco
Public Utilities, General Disclosures [Line Items]
Approved return rate on equity							10.50%				13.15%
Minimum \| Enhanced stability reserve \| APSC \| Alagasco
Public Utilities, General Disclosures [Line Items]
Extraordinary costs related to a single force majeure event limit									0.3
Extraordinary costs related to multiple force majeure events limit									0.4
Negative individual large commercial and industrial customer budget revenue variance minimum amount									$ 0.4
Maximum \| APSC \| Alagasco
Public Utilities, General Disclosures [Line Items]
Approved return rate on equity							10.95%				13.65%
Scenario, Forecast \| ISRS charges from March 2014 - August 2014 \| MoPSC \| Laclede Gas
Public Utilities, General Disclosures [Line Items]
Approved rate increase		$ 19.6
Scenario, Forecast \| ISRS charges from March 2014 - August 2014 \| MoPSC \| Missouri Gas Energy (MGE)
Public Utilities, General Disclosures [Line Items]
Approved rate increase		$ 6.7
Scenario, Forecast \| Enhanced stability reserve \| APSC \| Alagasco
Public Utilities, General Disclosures [Line Items]
Revenue subject to refund amortization period	5 years
Revenue subject to refund annual amortization limit	$ 0.7