Accrued Asset Recovery Damaged Property Costs, Storm Reserve

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- Definition

Accrued reserve to cover cost of damages.

+ References

No definition available.

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- Definition

Approved Annual Property Damage Reserve Accrual

+ References

No definition available.

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- Definition

Cumulative Costs Limit

+ References

No definition available.

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- Definition

Customer Surcharge Storm Recovery Capacity

+ References

No definition available.

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- Definition

Monthly Customer Surcharge Storm Recovery Costs

+ References

No definition available.

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- Definition

Property Damage Reserve, Percentage of Balance

+ References

No definition available.

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- Definition

Recovery Period For Natural Disaster Reserve Costs

+ References

No definition available.

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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)
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- Definition

Amount of inventory reserves for last-in first-out (LIFO) and other inventory valuation methods.

+ References

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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.

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- Definition

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

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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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Introduction - Narrative (Details)			3 Months Ended		6 Months Ended	9 Months Ended
Introduction - Narrative (Details)	Apr. 04, 2017 USD ($)	Apr. 01, 2017	Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($)	Jun. 30, 2016 USD ($)	Sep. 30, 2017 USD ($) kWh
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		$ 39,000,000			$ 39,000,000
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
Accrued storm reserve damaged property costs			40,000,000			40,000,000
SOUTHERN Co GAS \| GEORGIA POWER CO
Related Party Transaction [Line Items]
Related party transactions				$ 7,000,000		18,000,000
SOUTHERN Co GAS \| SOUTHERN POWER CO
Related Party Transaction [Line Items]
Related party transactions				2,000,000		94,000,000
Southern Natural Gas Company, LLC \| SOUTHERN Co GAS
Related Party Transaction [Line Items]
Related party transactions				4,000,000		24,000,000
Southern Natural Gas Company, LLC \| ALABAMA POWER CO
Related Party Transaction [Line Items]
Related party transactions				1,000,000		8,000,000
Southern Natural Gas Company, LLC \| GEORGIA POWER CO
Related Party Transaction [Line Items]
Related party transactions				8,000,000		77,000,000
Southern Natural Gas Company, LLC \| SOUTHERN POWER CO
Related Party Transaction [Line Items]
Related party transactions				2,000,000		19,000,000
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 decrement			0			$ 0
Inventory write-down			$ 0	$ 0		$ 0
Predecessor \| Wholesale Gas Services \| SOUTHERN Co GAS
Related Party Transaction [Line Items]
Inventory write-down					$ 0