Fair Value Measurements (Details 1) (USD $) In Millions	Jun. 30, 2011
Alabama Power [Member] | Trust owned life insurance [Member]
Fair value measurements of investments calculated at net asset value per share as well as the nature and risk of those investments
Fair Value	$ 90
Unfunded Commitments	0
Redemption Frequency	Daily
Redemption Notice Period	15 days
Alabama Power [Member] | Money market funds [Member]
Fair value measurements of investments calculated at net asset value per share as well as the nature and risk of those investments
Fair Value	41
Unfunded Commitments	0
Redemption Frequency	Daily
Redemption Notice Period	Not applicable
Georgia Power [Member] | Corporate bonds - commingled funds [Member]
Fair value measurements of investments calculated at net asset value per share as well as the nature and risk of those investments
Fair Value	82
Unfunded Commitments	0
Redemption Frequency	Daily
Redemption Notice Period	1 to 3 days
Georgia Power [Member] | Other - commingled funds [Member]
Fair value measurements of investments calculated at net asset value per share as well as the nature and risk of those investments
Fair Value	40
Unfunded Commitments	0
Redemption Frequency	Daily
Redemption Notice Period	Not applicable
Georgia Power [Member] | Money market funds [Member]
Fair value measurements of investments calculated at net asset value per share as well as the nature and risk of those investments
Fair Value	8
Unfunded Commitments	0
Redemption Frequency	Daily
Redemption Notice Period	Not applicable
Gulf Power [Member] | Money market funds [Member]
Fair value measurements of investments calculated at net asset value per share as well as the nature and risk of those investments
Fair Value	14
Unfunded Commitments	0
Redemption Frequency	Daily
Redemption Notice Period	Not applicable
Mississippi Power [Member] | Money market funds [Member]
Fair value measurements of investments calculated at net asset value per share as well as the nature and risk of those investments
Fair Value	48
Unfunded Commitments	0
Redemption Frequency	Daily
Redemption Notice Period	Not applicable
Corporate bonds - commingled funds [Member]
Fair value measurements of investments calculated at net asset value per share as well as the nature and risk of those investments
Fair Value	82
Unfunded Commitments	0
Redemption Frequency	Daily
Redemption Notice Period	1 to 3 days
Other - commingled funds [Member]
Fair value measurements of investments calculated at net asset value per share as well as the nature and risk of those investments
Fair Value	40
Unfunded Commitments	0
Redemption Frequency	Daily
Redemption Notice Period	Not applicable
Trust owned life insurance [Member]
Fair value measurements of investments calculated at net asset value per share as well as the nature and risk of those investments
Fair Value	90
Unfunded Commitments	0
Redemption Frequency	Daily
Redemption Notice Period	15 days
Money market funds [Member]
Fair value measurements of investments calculated at net asset value per share as well as the nature and risk of those investments
Fair Value	254
Unfunded Commitments	$ 0
Redemption Frequency	Daily
Redemption Notice Period	Not applicable