Asset Retirement Obligation, Period Of Update Cycle

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- Definition

Number Of Agreements for Renewable Generation

+ References

No definition available.

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- Definition

Number Of Military Bases For Renewable Generation

+ References

No definition available.

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

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- Definition

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).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(k)(1))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(a))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16212-109274

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph ((a)(1),(b))
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

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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
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39603-107864

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
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-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

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-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39622-107864

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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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Introduction - Narrative (Details) $ in Millions	1 Months Ended	9 Months Ended	33 Months Ended
Introduction - Narrative (Details) $ in Millions	Sep. 30, 2016 USD ($) location	Sep. 30, 2016 USD ($) location	Sep. 30, 2016 USD ($) agreement location	Jul. 10, 2016	Dec. 31, 2015 USD ($)
Related Party Transaction [Line Items]
Construction work in progress	$ 10,069.0	$ 10,069.0	$ 10,069.0		$ 9,082.0
Other intangible assets, net of amortization	$ 942.0	$ 942.0	$ 942.0		317.0
Georgia Power [Member]
Related Party Transaction [Line Items]
Number of military bases for renewable generation \| location	2	2	2
Construction work in progress	$ 4,888.0	$ 4,888.0	$ 4,888.0		4,775.0
Due to related parties current	451.0	$ 451.0	451.0		411.0
ARO period of update cycle		3 years
Alabama Power [Member]
Related Party Transaction [Line Items]
Construction work in progress	473.0	$ 473.0	473.0		801.0
Due to related parties current	309.0	309.0	309.0		278.0
Southern Power [Member]
Related Party Transaction [Line Items]
Construction work in progress	1,652.0	1,652.0	1,652.0		1,137.0
Due to related parties current	91.0	91.0	91.0		66.0
Other intangible assets, net of amortization	389.0	389.0	$ 389.0		$ 317.0
Affiliated Entity [Member] \| Georgia Power [Member]
Related Party Transaction [Line Items]
Number of agreements for renewable generation \| agreement			2
PowerSecure International, Inc. [Member] \| Georgia Power [Member]
Related Party Transaction [Line Items]
Construction work in progress	108.0	108.0	$ 108.0
Due to related parties current	0.2	$ 0.2	$ 0.2
Southern Natural Gas Company, LLC [Member] \| Georgia Power [Member]
Related Party Transaction [Line Items]
Related party transactions	8.0
Southern Natural Gas Company, LLC [Member] \| Southern Company [Member]
Related Party Transaction [Line Items]
Related party transactions	16.0
Southern Natural Gas Company, LLC [Member] \| Alabama Power [Member]
Related Party Transaction [Line Items]
Related party transactions	1.0
Southern Natural Gas Company, LLC [Member] \| Southern Power [Member]
Related Party Transaction [Line Items]
Related party transactions	$ 2.0
Southern Natural Gas Company, LLC [Member]
Related Party Transaction [Line Items]
Noncontrolling interest, ownership percentage by parent				50.00%