Introduction - Narrative (Details) $ in Millions	30 Months Ended
Jun. 30, 2016 USD ($) agreement location	Dec. 31, 2015 USD ($)
Related Party Transaction [Line Items]
Intangible Assets, Net (Excluding Goodwill)	$ 490	$ 317
Construction work in progress	9,451	9,082
Southern Power [Member]
Related Party Transaction [Line Items]
Intangible Assets, Net (Excluding Goodwill)	316	317
Construction work in progress	1,852	1,137
Due to Related Parties, Current	$ 80	66
Georgia Power [Member]
Related Party Transaction [Line Items]
Number Of Military Bases For Renewable Generation \| location	2
Construction work in progress	$ 4,655	4,775
Due to Related Parties, Current	$ 407	$ 411
Affiliated Entity [Member] \| Georgia Power [Member]
Related Party Transaction [Line Items]
Number Of Agreements for Renewable Generation \| agreement	2
Construction work in progress	$ 102
Due to Related Parties, Current	$ 13

Number Of Agreements for Renewable Generation

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Number Of Military Bases For Renewable Generation

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- Definition

Amount of structure or a modification to a structure under construction. Includes recently completed structures or modifications to structures that have not been placed into service.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
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Carrying amount as of the balance sheet date of obligations due all related parties. For classified balance sheets, represents the current portion of such liabilities (due within one year or within the normal operating cycle if longer).

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
-Paragraph 1
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Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

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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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