Fair Value Measurements (Details Textual) (USD $) In Millions	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2011
Fair Value Measurements (Textuals) [Abstract]
Increase in fair value of the funds, including reinvested interest and dividends	$ 16	$ 58
Fair Value Measurement (Textual) [Abstract]
Maximum number of months related to maturities in the portfolio not to exceeded from the date of purchase		13 months
Maximum number of days related to dollar-weighted average portfolio maturities regarding commingled funds		90 days
Minimum number of months related to the reset date of maturities in the portfolio with put features or floating rates		13 months
Maximum maturity for longer term investment grade fixed income obligations (in years)		5 years
Alabama Power [Member]
Fair Value Measurements (Textuals) [Abstract]
Increase in fair value of the funds, including reinvested interest and dividends	4	31
Georgia Power [Member]
Fair Value Measurements (Textuals) [Abstract]
Increase in fair value of the funds, including reinvested interest and dividends	12	27
Nuclear decommissioning trusts	$ 119	$ 119

Fair Value Measurements Textuals Abstract.

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Fair Value Measurement Textual Abstract.

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Increase in fair value of the funds, including reinvested interest and dividends.

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Maximum maturity for longer term investment grade fixed income obligations.

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Maximum number of days related to dollar weighted average portfolio maturities regarding commingled funds.

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Maximum number of months related to maturities in the portfolio not to exceeded from the date of purchase.

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Minimum number of months related to the reset date of maturities in the portfolio with put features or floating rates.

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The fair value of investments held in a trust fund to pay for the costs of decontaminating and decommissioning facilities, whether such amount is presented as a separate caption or as a parenthetical disclosure on the balance sheet. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 143
-Paragraph 22
-Subparagraph b
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

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