Accrued reserve to cover cost of damages.

No definition available.

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- Definition

Approved Annual Property Damage Reserve Accrual

+ References

No definition available.

+ Details

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- Definition

Cumulative Costs Limit

+ References

No definition available.

+ Details

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- Definition

Customer Surcharge Storm Recovery Capacity

+ References

No definition available.

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- Definition

Customer Surcharge Storm Recovery Costs

+ References

No definition available.

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- Definition

Property Damage Reserve, Percentage of Balance

+ References

No definition available.

+ Details

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- Definition

Recovery Period For Natural Disaster Reserve Costs

+ References

No definition available.

+ Details

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- Definition

The increase (decrease) during the reporting period in the public utility damage costs that will be permitted by regulatory agencies to be recovered from rate payers.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

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- Definition

Amount of loss from reductions in inventory due to subsequent measurement adjustments, including, but not limited to, physical deterioration, obsolescence, or changes in price levels.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 330
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=66092785&loc=d3e4542-108314

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-Section 35
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-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.2)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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-SubTopic 10
-Section 35
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=68049868&loc=SL66093879-108312

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- Definition

Amount of transactions with related party during the financial reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 3
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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.

+ References

No definition available.

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- Details

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- Details

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- Details

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Introduction - Narrative (Details)			3 Months Ended		6 Months Ended
Introduction - Narrative (Details)	Apr. 04, 2017 USD ($)	Apr. 01, 2017	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)	Jun. 30, 2017 USD ($) kWh	Jun. 30, 2016 USD ($)
GEORGIA POWER CO
Related Party Transaction [Line Items]
Property damage reserve, percentage of balance		0.75
GULF POWER CO
Related Party Transaction [Line Items]
PSC approved annual property damage reserve accrual	$ 3,500,000
Number of agreements for renewable generation	0		$ 40,000,000		$ 40,000,000
Increase (decrease) in recoverable property damage costs	$ 31,000,000
Recovery period for natural disaster reserve costs					60 days
Cumulative costs limit under PSC order					$ 100,000,000
SOUTHERN Co GAS \| GEORGIA POWER CO
Related Party Transaction [Line Items]
Related party transactions					9,000,000
SOUTHERN Co GAS \| SOUTHERN POWER CO
Related Party Transaction [Line Items]
Related party transactions					56,000,000
Southern Natural Gas Company, LLC \| SOUTHERN Co GAS
Related Party Transaction [Line Items]
Related party transactions					16,000,000
Southern Natural Gas Company, LLC \| ALABAMA POWER CO
Related Party Transaction [Line Items]
Related party transactions					4,000,000
Southern Natural Gas Company, LLC \| GEORGIA POWER CO
Related Party Transaction [Line Items]
Related party transactions					51,000,000
Southern Natural Gas Company, LLC \| SOUTHERN POWER CO
Related Party Transaction [Line Items]
Related party transactions					13,000,000
Maximum \| GULF POWER CO
Related Party Transaction [Line Items]
Customer surcharge storm recovery costs					$ 4.00
Customer surcharge storm recovery capacity \| kWh					1,000
Wholesale Gas Services \| SOUTHERN Co GAS
Related Party Transaction [Line Items]
Inventory write-down					$ 0
Predecessor \| Wholesale Gas Services \| SOUTHERN Co GAS
Related Party Transaction [Line Items]
Inventory write-down			$ 0	$ 0		$ 0