Common Stock and Stock Compensation - Textual (Details) (USD $)	6 Months Ended	12 Months Ended
	Dec. 31, 2013 Employee	Dec. 31, 2013 Employee	Dec. 31, 2012	Dec. 31, 2011
Share-based Compensation [Abstract]
Stock Issued During Period, Shares, Southern Investment Plan and employee and director stock plans		6,900,000	12,100,000
Stock Issued During Period, Value, Southern Investment Plan and employee and director stock plans		$ 222,400,000	$ 397,000,000
Common Stock Shares Issued Previously Held In Treasury	4,400,000
Common Stock Previously Held In Treasury Amount	183,600,000
Common Stock Shares Issued Through At-The-Market Issuances	8,000,000
Common Stock Issued Through At-The-Market Issuances Amount	327,300,000
Common Stock Fees And Commissions	2,800,000
Share-based compensation arrangement by Share-based payment award, number of shares reserved for issuance, pursuant to Stock-based compensation plan		116,000,000
Number of employees participating in stock option program	5,776	5,776
Weighted average remaining contractual term for options outstanding		6 years
Weighted average remaining contractual term for options exercisable		5 years
Aggregate intrinsic value for options outstanding	147,000,000	147,000,000
Aggregate intrinsic value for options exercisable	142,000,000	142,000,000
Total unrecognized compensation cost related to award	9,000,000	9,000,000
Total compensation cost for award recognized in income		25,000,000	23,000,000	22,000,000
Total compensation cost for award recognized in income, tax benefit		10,000,000	9,000,000	8,000,000
Total intrinsic value of options exercised		77,000,000	162,000,000	155,000,000
Actual tax benefit for the tax deduction from stock option exercised		30,000,000	62,000,000	60,000,000
Cash received from issuance related to option exercise		204,000,000	397,000,000	528,000,000
Minimum Percentage of transfer performance shares to common stock based on actual Total Shareholder Return		0.00%
Maximum Percentage of transfer performance shares to common stock based on actual Total Shareholder Return		200.00%
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount		16,000,000
Undistributed retained earnings of the subsidiaries		6,100,000,000
Performance Shares [Member]
Share-based Compensation [Abstract]
Stock Issued During Period, Shares, Southern Investment Plan and employee and director stock plans		700,000
Stock Options [Member]
Share-based Compensation [Abstract]
Option expiration period from date of grant		10 years
Total unrecognized compensation cost related to award, weighted average period		11 months
Performance Share Plan [Member]
Share-based Compensation [Abstract]
Total unrecognized compensation cost related to award	35,000,000	35,000,000
Total unrecognized compensation cost related to award, weighted average period		11 months
Total compensation cost for award recognized in income		31,000,000	28,000,000	18,000,000
Total compensation cost for award recognized in income, tax benefit		12,000,000	11,000,000	7,000,000
Vesting period of performance share units issued under Performance Share Plan		3 years
Performance share units, unvested	1,643,759	1,643,759	1,633,156
Performance share units, granted		929,653
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period		807,702
Performance unit shares, forfeited		111,348
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Number	240,980	240,980
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Exercise Price	$ 41.27	$ 41.27
Maximum [Member] | Stock Options [Member]
Share-based Compensation [Abstract]
Share Based Compensation Arrangement by Share Based Payment Award Exercisable Period		3 years
Southern Company Common Stock [Member]
Share-based Compensation [Abstract]
Remaining shares available for awards	28,000,000	28,000,000
Alabama Power [Member]
Share-based Compensation [Abstract]
Remaining shares available for awards	28,000,000	28,000,000
Number of employees participating in stock option program	1,000	1,000
Weighted average remaining contractual term for options outstanding		6 years
Weighted average remaining contractual term for options exercisable		5 years
Aggregate intrinsic value for options outstanding	26,000,000	26,000,000
Aggregate intrinsic value for options exercisable	25,000,000	25,000,000
Total unrecognized compensation cost related to award	1,000,000	1,000,000
Total unrecognized compensation cost related to award, weighted average period		11 months
Total compensation cost for award recognized in income		4,000,000	4,000,000	3,000,000
Total compensation cost for award recognized in income, tax benefit		2,000,000	1,000,000	1,000,000
Total intrinsic value of options exercised		11,000,000	28,000,000	23,000,000
Actual tax benefit for the tax deduction from stock option exercised		4,000,000	11,000,000	9,000,000
Alabama Power [Member] | Performance Shares [Member]
Share-based Compensation [Abstract]
Total unrecognized compensation cost related to award	6,000,000	6,000,000
Total unrecognized compensation cost related to award, weighted average period		11 months
Total compensation cost for award recognized in income		5,000,000	5,000,000	3,000,000
Total compensation cost for award recognized in income, tax benefit		2,000,000	2,000,000	1,000,000
Vesting period of performance share units issued under Performance Share Plan		3 years
Minimum Percentage of transfer performance shares to common stock based on actual Total Shareholder Return		0.00%
Maximum Percentage of transfer performance shares to common stock based on actual Total Shareholder Return		200.00%
Performance share units, unvested	284,826	284,826	280,536
Performance share units, granted		141,355
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period		131,581
Performance unit shares, forfeited		5,484
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Number	39,258	39,258
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Exercise Price	$ 41.27	$ 41.27
Alabama Power [Member] | Stock Options [Member]
Share-based Compensation [Abstract]
Option expiration period from date of grant		10 years
Alabama Power [Member] | Maximum [Member] | Stock Options [Member]
Share-based Compensation [Abstract]
Share Based Compensation Arrangement by Share Based Payment Award Exercisable Period		3 years
Georgia Power [Member]
Share-based Compensation [Abstract]
Remaining shares available for awards	28,000,000	28,000,000
Number of employees participating in stock option program	1,265	1,265
Option expiration period from date of grant		10 years
Weighted average remaining contractual term for options outstanding		6 years
Weighted average remaining contractual term for options exercisable		5 years
Aggregate intrinsic value for options outstanding	27,000,000	27,000,000
Aggregate intrinsic value for options exercisable	26,000,000	26,000,000
Total intrinsic value of options exercised		16,000,000	34,000,000	32,000,000
Actual tax benefit for the tax deduction from stock option exercised		6,000,000	13,000,000	12,000,000
Vesting period of performance share units issued under Performance Share Plan		3 years
Minimum Percentage of transfer performance shares to common stock based on actual Total Shareholder Return		0.00%
Maximum Percentage of transfer performance shares to common stock based on actual Total Shareholder Return		200.00%
Georgia Power [Member] | Performance Shares [Member]
Share-based Compensation [Abstract]
Vesting period of performance share units issued under Performance Share Plan		3 years
Performance share units, unvested	273,100	273,100	280,000
Performance share units, granted		161,240
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period		151,769
Performance unit shares, forfeited		16,371
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Number	45,239	45,239
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Exercise Price	$ 41.27	$ 41.27
Georgia Power [Member] | Performance Share Plan [Member]
Share-based Compensation [Abstract]
Total unrecognized compensation cost related to award	6,000,000	6,000,000
Total unrecognized compensation cost related to award, weighted average period		11 months
Total compensation cost for award recognized in income		6,000,000	6,000,000	4,000,000
Total compensation cost for award recognized in income, tax benefit		2,000,000	2,000,000	1,000,000
Georgia Power [Member] | Maximum [Member] | Stock Options [Member]
Share-based Compensation [Abstract]
Share Based Compensation Arrangement by Share Based Payment Award Exercisable Period		3 years
Gulf Power [Member]
Share-based Compensation [Abstract]
Number of employees participating in stock option program	211	211
Option expiration period from date of grant		10 years
Weighted average remaining contractual term for options outstanding		6 years
Weighted average remaining contractual term for options exercisable		5 years
Aggregate intrinsic value for options outstanding	5,700,000	5,700,000
Aggregate intrinsic value for options exercisable	5,500,000	5,500,000
Total unrecognized compensation cost related to award	400,000	400,000
Total unrecognized compensation cost related to award, weighted average period		11 months
Total compensation cost for award recognized in income		700,000
Total compensation cost for award recognized in income, tax benefit		300,000
Total intrinsic value of options exercised		1,700,000	3,800,000	3,200,000
Actual tax benefit for the tax deduction from stock option exercised		600,000	1,500,000	1,200,000
Vesting period of performance share units issued under Performance Share Plan		3 years
Minimum Percentage of transfer performance shares to common stock based on actual Total Shareholder Return		0.00%
Maximum Percentage of transfer performance shares to common stock based on actual Total Shareholder Return		200.00%
Gulf Power [Member] | Performance Shares [Member]
Share-based Compensation [Abstract]
Total unrecognized compensation cost related to award	1,200,000	1,200,000
Total compensation cost for award recognized in income		1,000,000	1,000,000	700,000
Total compensation cost for award recognized in income, tax benefit		400,000	400,000	300,000
Gulf Power [Member] | Performance Share Plan [Member]
Share-based Compensation [Abstract]
Total unrecognized compensation cost related to award, weighted average period		11 months
Vesting period of performance share units issued under Performance Share Plan		3 years
Performance share units, unvested	72,590	72,590	68,805
Performance share units, granted		30,627
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period		25,102
Performance unit shares, forfeited		1,740
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Number	7,476	7,476
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Exercise Price	$ 41.27	$ 41.27
Gulf Power [Member] | Maximum [Member] | Stock Options [Member]
Share-based Compensation [Abstract]
Share Based Compensation Arrangement by Share Based Payment Award Exercisable Period		3 years
Gulf Power [Member] | Southern Company Common Stock [Member]
Share-based Compensation [Abstract]
Remaining shares available for awards	28,000,000	28,000,000
Mississippi Power [Member]
Share-based Compensation [Abstract]
Vesting period of performance share units issued under Performance Share Plan		3 years
Mississippi Power [Member] | Performance Shares [Member]
Share-based Compensation [Abstract]
Total unrecognized compensation cost related to award	1,700,000	1,700,000
Total unrecognized compensation cost related to award, weighted average period		11 months
Total compensation cost for award recognized in income		1,500,000	1,200,000	700,000
Total compensation cost for award recognized in income, tax benefit		600,000	400,000	300,000
Vesting period of performance share units issued under Performance Share Plan		3 years
Minimum Percentage of transfer performance shares to common stock based on actual Total Shareholder Return		0.00%
Maximum Percentage of transfer performance shares to common stock based on actual Total Shareholder Return		200.00%
Performance share units, unvested	41,537	41,537	68,486
Performance share units, granted		36,769
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period		48,019
Performance unit shares, forfeited		15,699
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Number	14,341	14,341
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Exercise Price	$ 41.27	$ 41.27
Mississippi Power [Member] | Stock Options [Member]
Share-based Compensation [Abstract]
Remaining shares available for awards	28,000,000	28,000,000
Number of employees participating in stock option program	236	236
Option expiration period from date of grant		10 years
Weighted average remaining contractual term for options outstanding		6 years
Weighted average remaining contractual term for options exercisable		4 years
Aggregate intrinsic value for options outstanding	4,600,000	4,600,000
Aggregate intrinsic value for options exercisable	4,400,000	4,400,000
Total unrecognized compensation cost related to award	300,000	300,000
Total unrecognized compensation cost related to award, weighted average period		10 months
Total compensation cost for award recognized in income		1,000,000	900,000	800,000
Total compensation cost for award recognized in income, tax benefit		400,000	300,000	300,000
Total intrinsic value of options exercised		2,700,000	4,900,000	4,200,000
Actual tax benefit for the tax deduction from stock option exercised		$ 1,100,000	$ 1,900,000	$ 1,600,000
Mississippi Power [Member] | Maximum [Member] | Stock Options [Member]
Share-based Compensation [Abstract]
Share Based Compensation Arrangement by Share Based Payment Award Exercisable Period		3 years