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- Definition

Public Utilities, Approved Customer Credit, Amount

+ References

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- Definition

Amount awarded from other party in judgment or settlement of litigation.

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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 approved rate increase (decrease) by regulatory agency.

+ References

No definition available.

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- Definition

Percentage of public utility's approved return on equity.

+ References

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Percentage of public utility's interim rate increase (decrease) allowed while waiting final decision of regulatory agency.

+ References

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- Definition

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

+ References

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- Definition

Percentage of public utility's requested return on equity.

+ References

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- Definition

The amount for the individual regulatory liability as itemized in a table of regulatory liabilities as of the end of the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 980
-SubTopic 405
-Section 25
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6500807&loc=d3e48068-110394

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Contingencies and Regulatory Matters - Southern Company Gas (Details) - USD ($) $ in Millions						1 Months Ended		3 Months Ended
	Oct. 25, 2018	Oct. 15, 2018	May 15, 2018	May 02, 2018	Feb. 23, 2018	Oct. 31, 2018	Jul. 31, 2018	Mar. 31, 2018	Sep. 30, 2018
Florida City Gas
Loss Contingencies [Line Items]
Public utilities, interim rate increase (decrease), percentage			4.00%
Public utilities, approved return on equity percentage			55.00%
Atlanta Gas Light
Loss Contingencies [Line Items]
Public utilities, requested rate increase (decrease), amount					$ (16)
Customer credit							$ 8
Atlanta Gas Light \| Pipeline Replacement Program
Loss Contingencies [Line Items]
Litigation settlement awarded from other party								$ 7
Atlanta Gas Light \| Subsequent Event
Loss Contingencies [Line Items]
Customer credit						$ 8
Nicor Gas
Loss Contingencies [Line Items]
Public utilities, approved return on equity percentage				9.80%
Approved decrease in fuel rates amount				$ 44
Chattanooga Gas \| Subsequent Event
Loss Contingencies [Line Items]
Public utilities, requested rate increase (decrease), amount		$ 1
Public utilities, requested return on equity, percentage		9.80%
Virginia Natural Gas \| Impact of Tax Reform Legislation
Loss Contingencies [Line Items]
Regulatory liabilities									$ 9
Virginia Natural Gas \| Subsequent Event
Loss Contingencies [Line Items]
Customer refund	$ 14
Minimum \| Florida City Gas
Loss Contingencies [Line Items]
Public utilities, requested return on equity, percentage					10.55%
Maximum \| Florida City Gas
Loss Contingencies [Line Items]
Public utilities, requested return on equity, percentage			10.95%