Electric Generating Units, Capacity

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- Definition

Guarantee of Unsecured Senior Notes

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- Definition

Joint ownership agreements.

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- Definition

jointly owned affiliate equity

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- Definition

Jointly Owned Affiliate Long Term Debt

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- Definition

Jointly Owned Affiliate Long Term Debt Annual Interest Requirement

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No definition available.

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- Definition

Jointly owned utility plant interests.

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No definition available.

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- Definition

Share Of Purchased Power

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No definition available.

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- Definition

Unconditional Guarantee To Pay Outstanding Pollution Control Revenue Bond Principal

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No definition available.

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- Definition

This item represents disclosure of the amount of dividends or other distributions received from unconsolidated subsidiaries, certain corporate joint ventures, and certain noncontrolled corporation; these investments are accounted for under the equity method of accounting. This element excludes distributions that constitute a return of investment, which are classified as investing activities.

+ 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 (b)
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-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 13
-Article 5

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
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- Definition

The period end amount owned by the reporting utility of a jointly owned utility plant in service.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 980
-SubTopic 360
-Section S99
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-Name Staff Accounting Bulletin (SAB)
-Number Topic 10
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- Definition

The period end amount of construction work in progress at a jointly owned electricity generation plant.

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- Definition

The period end amount of accumulated depreciation in a jointly owned electricity generation plant.

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- Definition

The proportionate share of interest (percent) in a jointly owned utility plant.

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- Definition

Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or 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
-Topic 942
-SubTopic 210
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-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 13
-Subparagraph 2, 3
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Joint Ownership Agreements (Details)	12 Months Ended
Joint Ownership Agreements (Details)	Dec. 31, 2015 USD ($) MW	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)	Aug. 31, 2014 USD ($)
Joint Ownership Agreements (Textual) [Abstract]
Short-term Debt	$ 1,376,000,000	$ 803,000,000
Alabama Power [Member]
Jointly owned utility plant interests
Percent Ownership	14.00%
Joint Ownership Agreements (Textual) [Abstract]
Total Megawatt Capacity \| MW	1,000
Jointly Owned Affiliate Equity	$ 118,000,000
Jointly Owned Affiliate Long Term Debt	125,000,000
Jointly Owned Affiliate Long Term Debt Annual Interest Requirement	3,000,000
Short-term Debt	$ 0	0
Dividends paid by equity method investment		3,000,000	$ 7,000,000
Ownership percentage, equity method investment	50.00%
Alabama Power [Member] \| SEGCO [Member]
Joint Ownership Agreements (Textual) [Abstract]
Total Megawatt Capacity \| MW	1,020
Share Of Purchased Power	$ 76,000,000	84,000,000	88,000,000
Unconditional guarantee to pay outstanding pollution control revenue bond principal	25,000,000
Alabama Power [Member] \| SEGCO [Member]
Joint Ownership Agreements (Textual) [Abstract]
Short-term Debt	52,000,000
Alabama Power [Member] \| Senior notes due December 1, 2018 [Member] \| SEGCO [Member]
Joint Ownership Agreements (Textual) [Abstract]
Guarantee of unsecured senior notes	$ 100,000,000
Alabama Power [Member] \| Plant Miller (coal) Units 1 and 2 [Member]
Jointly owned utility plant interests
Percent Ownership	91.84%
Plant in Service	$ 1,518,000,000
Accumulated Depreciation	587,000,000
Construction Work in Progress	$ 63,000,000
Joint Ownership Agreements (Textual) [Abstract]
Total Megawatt Capacity \| MW	1,320
Alabama Power [Member] \| SEGCO [Member]
Jointly owned utility plant interests
Percent Ownership	86.00%
Alabama Power [Member] \| Greene County [Member]
Jointly owned utility plant interests
Percent Ownership	60.00%
Plant in Service	$ 159,000,000
Accumulated Depreciation	97,000,000
Construction Work in Progress	$ 20,000,000
Joint Ownership Agreements (Textual) [Abstract]
Total Megawatt Capacity \| MW	500
Georgia Power [Member]
Joint Ownership Agreements (Textual) [Abstract]
Short-term Debt	$ 158,000,000	156,000,000
Georgia Power [Member] \| SEGCO [Member]
Joint Ownership Agreements (Textual) [Abstract]
Share Of Purchased Power	$ 78,000,000	84,000,000
Georgia Power [Member] \| Purchased Power from Affiliates [Member] \| SEGCO [Member]
Joint Ownership Agreements (Textual) [Abstract]
Share Of Purchased Power			$ 91,000,000
Georgia Power [Member] \| Plant Vogtle Units 1 and 2 [Member]
Jointly owned utility plant interests
Percent Ownership	45.70%
Plant in Service	$ 3,503,000,000
Accumulated Depreciation	2,084,000,000
Construction Work in Progress	$ 63,000,000
Georgia Power [Member] \| Plant Hatch (nuclear) [Member]
Jointly owned utility plant interests
Percent Ownership	50.10%
Plant in Service	$ 1,230,000,000
Accumulated Depreciation	568,000,000
Construction Work in Progress	$ 90,000,000
Georgia Power [Member] \| Plant Scherer (coal) Units 1 and 2 [Member]
Jointly owned utility plant interests
Percent Ownership	8.40%
Plant in Service	$ 260,000,000
Accumulated Depreciation	86,000,000
Construction Work in Progress	$ 1,000,000
Georgia Power [Member] \| Plant Wansley (coal) [Member]
Jointly owned utility plant interests
Percent Ownership	53.50%
Plant in Service	$ 915,000,000
Accumulated Depreciation	290,000,000
Construction Work in Progress	$ 13,000,000
Georgia Power [Member] \| Rocky Mountain (pumped storage) [Member]
Jointly owned utility plant interests
Percent Ownership	25.40%
Plant in Service	$ 181,000,000
Accumulated Depreciation	125,000,000
Construction Work in Progress	$ 0
Georgia Power [Member] \| Intercession City (combustion turbine) [Member]
Jointly owned utility plant interests
Percent Ownership	33.30%
Plant in Service	$ 13,000,000
Accumulated Depreciation	4,000,000
Construction Work in Progress	$ 0
Georgia Power [Member] \| Vogtle Units 3 and 4 [Member]
Jointly owned utility plant interests
Percent Ownership	45.70%
Georgia Power [Member] \| Plant Scherer Unit 3 (coal) [Member]
Jointly owned utility plant interests
Percent Ownership	75.00%
Plant in Service	$ 1,223,000,000
Accumulated Depreciation	433,000,000
Construction Work in Progress	$ 1,000,000
Georgia Power [Member] \| Alabama Power [Member]
Joint Ownership Agreements (Textual) [Abstract]
Total Megawatt Capacity \| MW	1,020
Gulf Power [Member]
Joint Ownership Agreements (Textual) [Abstract]
Short-term Debt	$ 142,000,000	110,000,000
Gulf Power [Member] \| Plant Scherer Unit 3 (coal) [Member]
Jointly owned utility plant interests
Percent Ownership	25.00%
Plant in Service	$ 395,000,000
Accumulated Depreciation	136,000,000
Construction Work in Progress	$ 2,000,000
Joint Ownership Agreements (Textual) [Abstract]
Total Megawatt Capacity \| MW	818
Gulf Power [Member] \| Plant Daniel Units 1 &2 2 [Member]
Jointly owned utility plant interests
Percent Ownership	50.00%
Plant in Service	$ 669,000,000
Accumulated Depreciation	184,000,000
Construction Work in Progress	$ 9,000,000
Joint Ownership Agreements (Textual) [Abstract]
Total Megawatt Capacity \| MW	1,000
Mississippi Power [Member]
Joint Ownership Agreements (Textual) [Abstract]
Short-term Debt	$ 500,000,000	0
Mississippi Power [Member] \| Greene County [Member]
Jointly owned utility plant interests
Construction Work in Progress				$ 6,000,000
Mississippi Power [Member] \| Greene County [Member] \| Alabama Power [Member]
Jointly owned utility plant interests
Percent Ownership	40.00%
Plant in Service	$ 152,000,000
Accumulated Depreciation	56,000,000
Construction Work in Progress	$ 13,000,000
Joint Ownership Agreements (Textual) [Abstract]
Total Megawatt Capacity \| MW	500
Mississippi Power [Member] \| Plant Daniel Units 1 &2 2 [Member]
Jointly owned utility plant interests
Percent Ownership	50.00%
Mississippi Power [Member] \| Plant Daniel Units 1 &2 2 [Member] \| Gulf Power [Member]
Jointly owned utility plant interests
Percent Ownership	50.00%
Plant in Service	$ 686,000,000
Accumulated Depreciation	160,000,000
Construction Work in Progress	$ 10,000,000
Joint Ownership Agreements (Textual) [Abstract]
Total Megawatt Capacity \| MW	1,000
Southern Power [Member]
Joint Ownership Agreements (Textual) [Abstract]
Total Megawatt Capacity \| MW	659
Short-term Debt	$ 137,000,000	$ 195,000,000
Southern Power [Member] \| Plant Stanton (combined cycle) Unit A [Member]
Jointly owned utility plant interests
Percent Ownership	65.00%
Plant in Service	$ 157,000,000
Accumulated Depreciation	53,000,000
Construction Work in Progress	$ 0
Southern Power [Member] \| Plant Stanton (combined cycle) Unit A [Member] \| Orlando Utilities Commission [Member]
Jointly owned utility plant interests
Percent Ownership	28.00%
Southern Power [Member] \| Plant Stanton (combined cycle) Unit A [Member] \| Florida Municipal Power Agency [Member]
Jointly owned utility plant interests
Percent Ownership	3.50%
Southern Power [Member] \| Plant Stanton (combined cycle) Unit A [Member] \| Kissimmee Utility Authority [Member]
Jointly owned utility plant interests
Percent Ownership	3.50%