Contingencies and Regulatory Matters (Details) (USD $)	6 Months Ended	3 Months Ended		6 Months Ended			0 Months Ended	3 Months Ended		6 Months Ended		12 Months Ended					6 Months Ended		3 Months Ended		6 Months Ended		0 Months Ended		1 Months Ended		3 Months Ended		6 Months Ended		12 Months Ended										0 Months Ended	12 Months Ended	3 Months Ended	6 Months Ended		12 Months Ended	3 Months Ended		6 Months Ended		12 Months Ended			6 Months Ended		12 Months Ended					0 Months Ended		0 Months Ended
	Jun. 30, 2014	Jun. 30, 2014 Alabama Power [Member]	Jun. 30, 2013 Alabama Power [Member]	Jun. 30, 2014 Alabama Power [Member]	Jun. 30, 2013 Alabama Power [Member]	Dec. 31, 2013 Alabama Power [Member]	May 20, 2014 Georgia Power [Member] Purchased_Power_Agreement WindFarms	Jun. 30, 2014 Georgia Power [Member]	Jun. 30, 2013 Georgia Power [Member]	Jun. 30, 2014 Georgia Power [Member]	Jun. 30, 2013 Georgia Power [Member]	Dec. 31, 2013 Georgia Power [Member]	Jan. 02, 2014 Georgia Power [Member]	Jan. 02, 2013 Georgia Power [Member]	Jan. 02, 2012 Georgia Power [Member]	Jan. 02, 2011 Georgia Power [Member]	Jun. 30, 2014 Georgia Power [Member] Minimum [Member]	Jun. 30, 2014 Georgia Power [Member] Maximum [Member]	Jun. 30, 2014 Gulf Power [Member]	Jun. 30, 2013 Gulf Power [Member]	Jun. 30, 2014 Gulf Power [Member] clause	Jun. 30, 2013 Gulf Power [Member]	Jun. 24, 2014 Mississippi Power [Member]	May 20, 2014 Mississippi Power [Member]	Mar. 31, 2013 Mississippi Power [Member]	Mar. 31, 2012 Mississippi Power [Member]	Jun. 30, 2014 Mississippi Power [Member]	Jun. 30, 2013 Mississippi Power [Member]	Jun. 30, 2014 Mississippi Power [Member]	Jun. 30, 2013 Mississippi Power [Member]	Dec. 31, 2013 Mississippi Power [Member]	Dec. 31, 2012 Mississippi Power [Member]	May 06, 2014 Mississippi Power [Member]	Apr. 01, 2014 Mississippi Power [Member]	Jan. 02, 2014 Mississippi Power [Member]	Dec. 31, 2010 Mississippi Power [Member]	Jan. 31, 2013 Mississippi Power [Member] Maximum [Member]	Jun. 30, 2014 Gulf Power and Mississippi Power [Member]	May 20, 2014 Wind Farm [Member] Georgia Power [Member] MW	Jan. 10, 2014 Plant Mitchell Unit 3 [Member] Georgia Power [Member] MW	Feb. 26, 2013 Electricity Generation Plant, Non-Nuclear [Member] Mississippi Power [Member]	Dec. 31, 2012 Electricity Generation Plant, Non-Nuclear [Member] Mississippi Power [Member]	Jun. 30, 2013 Kemper IGCC [Member]	Jun. 30, 2014 Kemper IGCC [Member]	Jun. 30, 2013 Kemper IGCC [Member]	Dec. 31, 2013 Kemper IGCC [Member]	Mar. 31, 2014 Kemper IGCC [Member] Mississippi Power [Member]	Mar. 31, 2013 Kemper IGCC [Member] Mississippi Power [Member]	Jun. 30, 2014 Kemper IGCC [Member] Mississippi Power [Member]		Dec. 31, 2013 Kemper IGCC [Member] Mississippi Power [Member]	Dec. 31, 2012 Kemper IGCC [Member] Mississippi Power [Member]	Jun. 30, 2013 Kemper IGCC [Member] Mississippi Power [Member] MW	Jun. 30, 2014 Kemper IGCC [Member] Mississippi Power [Member] Minimum [Member]	Jun. 30, 2014 Kemper IGCC [Member] Mississippi Power [Member] Maximum [Member]	Dec. 31, 2010 Mine [Member] Mississippi Power [Member]	Jun. 30, 2014 Other deferred charges and assets [Member] Georgia Power [Member]	Dec. 31, 2013 Current Liabilities And Other Deferred Credits And Liabilities [Member] Georgia Power [Member]	Jun. 30, 2014 Storm Reserve [Member] Georgia Power [Member]	Dec. 31, 2013 Storm Reserve [Member] Georgia Power [Member]	Aug. 02, 2014 Subsequent Event [Member] Mississippi Power [Member]	Aug. 01, 2014 Subsequent Event [Member] Mississippi Power [Member]	Aug. 02, 2014 Subsequent Event [Member] Kemper IGCC [Member] Mississippi Power [Member]	Aug. 01, 2014 Subsequent Event [Member] Plant Watson Units 4 And 5 [Member] Mississippi Power [Member] MW	Aug. 01, 2014 Subsequent Event [Member] Plant Greene County Units 1 And 2 [Member] Mississippi Power [Member] MW	Aug. 01, 2014 Subsequent Event [Member] Plant Sweatt Units 1 And 2 [Member] Mississippi Power [Member] MW	Dec. 31, 2013 Non-Affiliate Capital Lease PPA [Member] Georgia Power [Member]	Jun. 30, 2014 Non-Affiliate Operating Lease PPA [Member] Georgia Power [Member]
Loss Contingencies [Line Items]
Projected Fuel Cost Over Or Under Recovery Threshold As Percentage Of Projected Fuel Revenue																					10.00%
Annual Retail Revenues																							$ 1,500,000
Number Of Wind PPAs							2
Number Of Wind Farms							2
Loss Contingency, Estimate of Possible Loss																											1,560,000,000		1,560,000,000
Environmental Matters
Civil penalties under Clean Air Act, per day, per violation, minimum	25,000
Civil penalties under Clean Air Act, per day, per violation, maximum	37,500
Environmental remediation liability								19,000,000		19,000,000									50,000,000		50,000,000						600,000		600,000
Civil penalties per day violation rate								37,500		37,500
Number of times of punitive damages in comparison to cost incurred by Environmental Protection Agency								3		3
Damages awarded				17,000,000						27,000,000
Increase in base rate under cost based electric tariff due to settlement																								10,100,000
Revenue to be received from increase in base rate																											6,900,000		6,900,000
Retail Regulatory Matters
Under recovered rate CNP balance		33,000,000		33,000,000		18,000,000
Under recovered rate CNP environmental balance		32,000,000		32,000,000		7,000,000
Over Recovered Fuel Cost																															14,500,000
Under recovered regulatory clause revenues																			43,400,000		43,400,000						14,500,000		14,500,000
Accumulated reserve balance for future storms		87,000,000		87,000,000		96,000,000
Over recovered fuel cost balance																																																									244,000,000	58,000,000
Under Recovered Fuel Balance Threshold																	200,000,000
Period Of Inaction By The Public Service Commission For Fuel Rates										30 days
Regulatory Assets																																																											107,000,000	37,000,000
PSC Retail Rate Increase																																	3,600,000
Percentage Of PSC Retail Rate Increase																																	0.38%
Proportionate share owed in consortium agreement										45.70%
Increase In NCCR Tariff													60,000,000	50,000,000	35,000,000	223,000,000
Amortization to earnings of financing costs capitalized over the five year period								91,000,000		91,000,000
Amortization to earnings of financing costs capitalized, amortization term										5 years
Costs included in CWIP								27,000,000		27,000,000																	3,010,000,000		3,010,000,000
Increase (decrease) in projected certified construction capital costs										5.00%
Estimated In-service Capital Cost																	4,400,000,000	4,800,000,000
Cost incurred by Mississippi Power associated with plant including regulatory filing costs												2,000,000,000
Construction Capital Costs												400,000,000
Reduction in projected in-service cost due to recovered cost										425,000,000
Reduction In Depreciation Expense																					62,500,000
Reduction In Depreciation Expense Year One																					5,400,000
Psc Approved Annual Property Damage Reserve Accrual																																		3,300,000
Ownership percentage in scrubber project																			50.00%		50.00%						50.00%		50.00%
Estimated cost of scrubber project																											330,000,000		330,000,000									660,000,000
Scrubber project expenditures amount																											213,700,000		213,700,000									419,600,000
Allowance For Funds Used During Construction Cost																													13,300,000
Integrated Coal Gasification Combined Cycle [Abstract]
Estimated Cost																																										2,400,000,000							3,810,000,000	[1]		2,880,000,000
Period Rate Plan For Cost Accrued Through Additional Prudence Review																													7 years
Revisions To Revenue Requirement																											50,000,000		50,000,000
Alternate Financing																																									1,000,000,000
Revenue Requirement Obligations																																																						130,000,000	160,000,000
Costs associated with CCP12 grant funds																																245,300,000
Maximum Cap Construction Cost																																																	4,670,000,000	[1],[2]
Pre-tax charge to income																																											450,000,000	380,000,000	990,000,000	1,180,000,000	380,000,000				1,180,000,000
After tax charge to income																																											277,900,000	234,700,000	611,300,000	728,700,000	234,700,000				728,700,000
Costs Due To Extension Of In-service Date																													20,000,000
Costs included in CWIP								27,000,000		27,000,000																	3,010,000,000		3,010,000,000
Cost deferred in other regulatory assets																											97,100,000		97,100,000
Other deferred charges and assets																											3,900,000		3,900,000
Previously expensed																											1,100,000		1,100,000
Settlement Agreement To Increase Rates																																					172,000,000
Amortization Period For Construction Project																													40 years
Increase Retail Rates In Year One																									15.00%
Increase Retail Rates In Year Two																													3.00%
Settlement Agreement Collection Amount To Mitigate Rate Impact Year Two																											156,000,000		156,000,000
Regulatory Liabilities																									172,400,000		74,300,000		74,300,000
Retail Revenues		1,249,000,000	1,221,000,000	2,546,000,000	2,362,000,000			2,000,000,000	1,879,000,000	4,050,000,000	3,608,000,000								310,344,000	305,550,000	613,464,000	565,427,000					211,326,000	214,254,000	418,364,000	382,564,000																		21,300,000	11,100,000
Reduced percentage interest transferred under asset purchase agreement																																15.00%
Term of Management Fee Contract																																																								40 years
Percentage of Carbon Dioxide Captured from Project																											70.00%		70.00%
Percentage of Contract to Purchase Carbon Dioxide from Project																											30.00%		30.00%
Purchase of Interest																																17.50%				17.50%
Deposit received																																150,000,000			75,000,000
Maximum period of discretion in the event senior unsecured credit rating falls																										15 days
Internal Revenue Code Section Forty Eight Tax Credits Phase I																													133,000,000
Internal Revenue Code Section Forty Eight Tax Credits Phase I I																													279,000,000
Minimum percentage of carbon dioxide that must be capture and sequester to remain eligible for the phase II tax credits																													65.00%
Tax Credit Carryforward, Amount																											276,400,000		276,400,000
Additional Bonus Depreciation For Property Acquired Future Periods																													50.00%
Positive Impact From Bonus Depreciation																																																	120,000,000
Electric Generating Units, Capacity																																							250	155													75											750	200	80
Capital Leases, Future Minimum Payments Due																																																																			641,000,000
Increase In Operating Leases Future Minimum Payments Due								127,000,000		127,000,000																																																										23,000,000
Operating Leases, Future Minimum Payments, Due in Two Years																																																																				116,000,000
Operating Leases, Future Minimum Payments, Due in Three Years																																																																				149,000,000
Operating Leases, Future Minimum Payments, Due in Four Years																																																																				150,000,000
Operating Leases, Future Minimum Payments, Due in Five Years																																																																				152,000,000
Operating Leases, Future Minimum Payments, Due Thereafter																																																																				1,700,000,000
Capacity Revenues Under Power Supply Agreement																															17,500,000
Number Of Regulatory Clauses																					4
Period Of Refraining From Intervening In Regulatory Proceedings																																																															3 years
Grant For Energy Efficiency And Renewable Program																																																														15,000,000
Period Of Grant For Energy Efficiency and Renewable Program																																																													5 years
Conservation Fund																																																														$ 2,000,000

[1] The 2012 MPSC CPCN Order approved a construction cost cap of up to $2.88 billion, net of the DOE Grants and excluding the Cost Cap Exceptions.

[2] Amounts in the Current Estimate reflect costs through May 31, 2015, but do not reflect any adjustments as a result of the expected placement of the combined cycle and the associated common facilities portion of the Kemper IGCC in service in the summer of 2014.