Accumulated Provisions for Decommissioning.

No definition available.

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- Definition

Amount expensed for rate making purpose.

+ References

No definition available.

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- Definition

Fair market value of fund's securities on loan under fund's managers securities lending program.

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- Definition

Fair value of collateral received amount.

+ References

No definition available.

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- Definition

Significant Assumption Of Inflation Rate Used To Determine Costs For Rate Making

+ References

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- Definition

Significant Assumption Of Trust Earnings Rate Used To Determine Costs For Rate Making

+ References

No definition available.

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- Definition

Amount of increase (decrease) in asset retirement obligations.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

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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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ASSET RETIREMENT OBLIGATIONS - Narrative (Details) - USD ($) $ in Millions	1 Months Ended			12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Jun. 30, 2018	Dec. 31, 2019	Dec. 31, 2014
Alabama Power
Jointly Owned Utility Plant Interests [Line Items]
Increase (decrease) to AROs			$ 1,200	$ 312
Estimated inflation rate (percentage)				4.50%
Estimated trust earnings rate (percentage)				7.00%
Alabama Power \| Internal reserves
Jointly Owned Utility Plant Interests [Line Items]
Accumulated provisions for decommissioning	$ 16	$ 17		$ 16
Alabama Power \| Plant Farley
Jointly Owned Utility Plant Interests [Line Items]
Increase (decrease) to AROs			300
Mississippi Power
Jointly Owned Utility Plant Interests [Line Items]
Increase (decrease) to AROs				57
Mississippi Power \| Plant Greene County
Jointly Owned Utility Plant Interests [Line Items]
Increase (decrease) to AROs			$ 11
Georgia Power
Jointly Owned Utility Plant Interests [Line Items]
Increase (decrease) to AROs	(174)	3,100
Fair market value of securities on loan and pledged to creditors	28	27		28
Fair value of collateral received	$ 29	28		$ 29
Estimated inflation rate (percentage)				2.75%
Estimated trust earnings rate (percentage)				4.75%
Georgia Power \| Plant Hatch and Plant Vogtle Units 1 And 2
Jointly Owned Utility Plant Interests [Line Items]
Increase (decrease) to AROs		$ 130
Annual decommissioning cost for ratemaking				$ 4	$ 5