Commitments (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Recorded Unconditional Purchase Obligation [Line Items]
Fuel expense	$ 5,510,000,000	$ 5,057,000,000	$ 6,262,000,000
Expense Under Purchase Power Agreements Accounted For As Operating Leases	157,000,000	171,000,000	199,000,000
Operating Leases, Rent Expense	123,000,000	155,000,000	176,000,000
Operating Leases, Future Minimum Payments Due, Next Twelve Months	101,000,000
Leasing commitment, 2015	75,000,000
Leasing commitment, 2016	65,000,000
Leasing commitment, 2017	44,000,000
Leasing commitment, 2018	31,000,000
Leasing commitment, 2019 and thereafter	135,000,000
Operating leases, future minimum lease payments due	451,000,000
Senior Notes	17,300,000,000	17,400,000,000
Barges and Rail Cars [Member]
Recorded Unconditional Purchase Obligation [Line Items]
Operating Leases, Future Minimum Payments Due, Next Twelve Months	56,000,000
Leasing commitment, 2015	35,000,000
Leasing commitment, 2016	30,000,000
Leasing commitment, 2017	12,000,000
Leasing commitment, 2018	6,000,000
Leasing commitment, 2019 and thereafter	15,000,000
Operating leases, future minimum lease payments due	154,000,000
Alabama Power and Georgia Power [Member]
Recorded Unconditional Purchase Obligation [Line Items]
Operating leases, future minimum lease payments due	59,000,000
Alabama Power [Member]
Recorded Unconditional Purchase Obligation [Line Items]
Fuel expense	1,631,000,000	1,503,000,000	1,679,000,000
Expense Under Purchase Power Agreements Accounted For As Operating Leases	30,000,000	33,000,000	33,000,000
Jointly Owned Utility Plant, Proportionate Ownership Share	14.00%
Operating Leases, Rent Expense	21,000,000	24,000,000	23,000,000
Operating Leases, Future Minimum Payments Due, Next Twelve Months	15,000,000
Leasing commitment, 2015	12,000,000
Leasing commitment, 2016	12,000,000
Leasing commitment, 2017	6,000,000
Leasing commitment, 2018	4,000,000
Leasing commitment, 2019 and thereafter	15,000,000
Operating leases, future minimum lease payments due	64,000,000
Long-term pollution control bonds	1,200,000,000	1,200,000,000
Alabama Power [Member] | Barges and Rail Cars [Member]
Recorded Unconditional Purchase Obligation [Line Items]
Operating Leases, Rent Expense	18,000,000	19,000,000	18,000,000
Alabama Power [Member] | Residual Value, Leased Property [Member]
Recorded Unconditional Purchase Obligation [Line Items]
Operating Leases, Future Minimum Payments Due, Next Twelve Months	8,000,000
Leasing commitment, 2015	5,000,000
Leasing commitment, 2016	4,000,000
Leasing commitment, 2018	0
Leasing commitment, 2019 and thereafter	12,000,000
Georgia Power [Member]
Recorded Unconditional Purchase Obligation [Line Items]
Fuel expense	2,307,000,000	2,051,000,000	2,789,000,000
Capacity Payments	27,000,000	50,000,000	52,000,000
Deferred capacity expense	162,000,000	169,000,000	216,000,000
Operating Leases, Rent Expense	32,000,000	34,000,000	33,000,000
Operating Leases, Future Minimum Payments Due, Next Twelve Months	26,000,000
Percentage Of Minimum Lease Payments	100.00%
Leasing commitment, 2015	20,000,000
Leasing commitment, 2016	13,000,000
Leasing commitment, 2017	9,000,000
Leasing commitment, 2018	6,000,000
Leasing commitment, 2019 and thereafter	11,000,000
Operating leases, future minimum lease payments due	85,000,000
Long-term pollution control bonds	1,700,000,000	1,800,000,000
Senior Notes	6,900,000,000	7,900,000,000
Period Of Service For Gas Transportation Supplier	1 year
Guarantor Obligations, Maximum Exposure, Undiscounted	43,000,000
Georgia Power [Member] | Plant McIntosh [Member]
Recorded Unconditional Purchase Obligation [Line Items]
Period Of Service For Gas Transportation Supplier	15 years
Georgia Power [Member] | MEAG Power [Member]
Recorded Unconditional Purchase Obligation [Line Items]
Jointly Owned Utility Plant, Proportionate Ownership Share	5.00%
Georgia Power [Member] | Alabama Power [Member] | Payment Guarantee [Member]
Recorded Unconditional Purchase Obligation [Line Items]
Long-term pollution control bonds	25,000,000
Georgia Power [Member] | Alabama Power [Member] | Financial Guarantee [Member]
Recorded Unconditional Purchase Obligation [Line Items]
Senior Notes	100,000,000
Georgia Power [Member] | Barges and Rail Cars [Member]
Recorded Unconditional Purchase Obligation [Line Items]
Operating Leases, Future Minimum Payments Due, Next Twelve Months	20,000,000
Leasing commitment, 2015	14,000,000
Leasing commitment, 2016	8,000,000
Leasing commitment, 2017	5,000,000
Leasing commitment, 2018	2,000,000
Leasing commitment, 2019 and thereafter	0
Operating leases, future minimum lease payments due	49,000,000
Georgia Power [Member] | Residual Value, Leased Property [Member] | 2018 [Member]
Recorded Unconditional Purchase Obligation [Line Items]
Operating leases, future minimum lease payments due	30,000,000
Gulf Power [Member]
Recorded Unconditional Purchase Obligation [Line Items]
Fuel expense	532,791,000	544,936,000	662,283,000
Expense Under Purchase Power Agreements Accounted For As Operating Leases	21,300,000	24,600,000	25,100,000
Deferred capacity expense	180,149,000	137,568,000
Operating Leases, Rent Expense	18,000,000	20,100,000	21,900,000
Operating Leases, Future Minimum Payments Due, Next Twelve Months	13,500,000
Number of Railcars Used Under Operating Lease	229
Leasing commitment, 2015	10,000,000
Leasing commitment, 2016	10,000,000
Leasing commitment, 2017	600,000
Operating leases, future minimum lease payments due	34,100,000
Long-term pollution control bonds	296,000,000	309,000,000
Senior Notes	945,000,000	945,000,000
Gulf Power [Member] | Plant Daniel [Member]
Recorded Unconditional Purchase Obligation [Line Items]
Long-term pollution control bonds	41,000,000
Gulf Power [Member] | Barges and Rail Cars [Member]
Recorded Unconditional Purchase Obligation [Line Items]
Operating Leases, Future Minimum Payments Due, Next Twelve Months	13,300,000
Leasing commitment, 2015	9,900,000
Leasing commitment, 2016	9,900,000
Leasing commitment, 2017	500,000
Operating leases, future minimum lease payments due	33,600,000
Gulf Power [Member] | Barges and Rail Cars [Member] | Plant Daniel [Member]
Recorded Unconditional Purchase Obligation [Line Items]
Operating Leases, Future Minimum Payments Due, Next Twelve Months	1,400,000
Fuel cost recovery clause	3,100,000	3,600,000	2,600,000
Leasing commitment, 2015	1,400,000
Leasing commitment, 2016	1,400,000
Leasing commitment, 2017	1,400,000
Leasing commitment, 2018	0
Mississippi Power [Member]
Recorded Unconditional Purchase Obligation [Line Items]
Fuel expense	491,250,000	411,226,000	490,415,000
Term of Management Fee Contract	40 years
Management fee	38,700,000
Operating Leases, Rent Expense	10,100,000	11,100,000	32,600,000
Number of Railcars Used Under Operating Lease	229
Company's share of the leases	50.00%
Fuel cost recovery clause	3,100,000	3,600,000	2,600,000
Long-term pollution control bonds	82,700,000	82,700,000
Senior Notes	1,100,000,000	1,100,000,000
Mississippi Power [Member] | Plant Daniel [Member]
Recorded Unconditional Purchase Obligation [Line Items]
Company's share of the leases	50.00%
Mississippi Power [Member] | Plant Watson [Member]
Recorded Unconditional Purchase Obligation [Line Items]
Company's share of the leases	100.00%
Mississippi Power [Member] | Barges and Rail Cars [Member]
Recorded Unconditional Purchase Obligation [Line Items]
Average leasing commitment, 2014	1,400,000
Average leasing commitment, 2015	1,400,000
Average leasing commitment, 2016	1,400,000
Average leasing commitment, 2017	1,400,000
Average leasing commitment, 2018	1,400,000
Mississippi Power [Member] | Fuel Handling Equipment [Member]
Recorded Unconditional Purchase Obligation [Line Items]
Operating Leases, Rent Expense	200,000	200,000	400,000
Operating Leases, Future Minimum Payments Due, Next Twelve Months	200,000
Leasing commitment, 2015	200,000
Leasing commitment, 2016	200,000
Mississippi Power [Member] | Barge Transportation [Member]
Recorded Unconditional Purchase Obligation [Line Items]
Operating Leases, Rent Expense	6,700,000	7,300,000	7,500,000
Operating Leases, Future Minimum Payments Due, Next Twelve Months	7,600,000
Leasing commitment, 2015	7,600,000
Leasing commitment, 2016	7,600,000
Southern Power [Member]
Recorded Unconditional Purchase Obligation [Line Items]
Fuel expense	473,805,000	426,257,000	454,790,000
Operating Leases, Rent Expense	1,900,000	800,000	600,000
Operating Leases, Future Minimum Payments Due, Next Twelve Months	2,700,000
Leasing commitment, 2015	2,500,000
Leasing commitment, 2016	2,500,000
Leasing commitment, 2017	2,500,000
Leasing commitment, 2018	2,600,000
Leasing commitment, 2019 and thereafter	83,900,000
Senior Notes	$ 1,600,000,000	$ 1,300,000,000