Georgia Power (GPJA) 10-Q 5 Aug 15 2015 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - Jun. 30, 2015 - shares	Total
Document Information [Line Items]
Entity Registrant Name	SOUTHERN CO
Entity Central Index Key	92,122
Document Type	10-Q
Document Period End Date	Jun. 30, 2015
Amendment Flag	false
Document Fiscal Year Focus	2,015
Document Fiscal Period Focus	Q2
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding	908,424,808
Alabama Power [Member]
Document Information [Line Items]
Entity Registrant Name	ALABAMA POWER CO
Entity Central Index Key	3,153
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding	30,537,500
Georgia Power [Member]
Document Information [Line Items]
Entity Registrant Name	GEORGIA POWER CO
Entity Central Index Key	41,091
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding	9,261,500
Gulf Power [Member]
Document Information [Line Items]
Entity Registrant Name	GULF POWER CO
Entity Central Index Key	44,545
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding	5,642,717
Mississippi Power [Member]
Document Information [Line Items]
Entity Registrant Name	MISSISSIPPI POWER CO
Entity Central Index Key	66,904
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding	1,121,000
Southern Power [Member]
Document Information [Line Items]
Entity Registrant Name	SOUTHERN POWER CO
Entity Central Index Key	1,160,661
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding	1,000

Condensed Consolidated Statemen

Condensed Consolidated Statements of Income (Unaudited) - USD ($) shares in Millions, $ in Millions		3 Months Ended			6 Months Ended
		Jun. 30, 2015		Jun. 30, 2014	Jun. 30, 2015		Jun. 30, 2014
Operating Revenues:
Total operating revenues		$ 4,337		$ 4,467	$ 8,520		$ 9,111
Other Income and (Expense):
Net Income (Loss) After Dividends on Preferred and Preference Stock of Subsidiaries	[1]	629	[2]	611	1,138	[3]	962	[3]
Southern Company [Member]
Operating Revenues:
Retail revenues		3,714		3,770	7,256		7,628
Wholesale revenues		448		515	915		1,119
Other electric revenues		162		169	325		334
Other revenues		13		13	24		30
Total operating revenues		4,337		4,467	8,520		9,111
Operating Expenses:
Fuel		1,200		1,462	2,412		3,109
Purchased power		171		133	315		320
Other operations and maintenance		1,100		1,019	2,222		2,005
Depreciation and amortization		500		504	987		1,001
Taxes other than income taxes		245		246	497		493
Estimated loss on Kemper IGCC		23		0	32		380
Total operating expenses		3,239		3,364	6,465		7,308
Operating Income (Loss)		1,098		1,103	2,055		1,803
Other Income and (Expense):
Allowance for equity funds used during construction		39		62	102		119
Interest expense, net of amounts capitalized		(180)		(210)	(393)		(416)
Other income (expense), net		(12)		(6)	(19)		(13)
Total other income and (expense)		(153)		(154)	(310)		(310)
Earnings Before Income Taxes		945		949	1,745		1,493
Income taxes (benefit)		302		321	576		497
Net Income (Loss)		643		628	1,169		996
Dividends on preferred and preference stock of subsidiaries		14		17	31		34
Net Income (Loss) After Dividends on Preferred and Preference Stock of Subsidiaries		$ 629		$ 611	$ 1,138		$ 962
Earnings per share (EPS) -
Basic EPS (in dollars per share)		$ 0.69		$ 0.68	$ 1.25		$ 1.08
Diluted EPS (in dollars per share)		$ 0.69		$ 0.68	$ 1.25		$ 1.07
Average number of shares of common stock outstanding (in millions)
Basic (in shares)		909		895	910		892
Diluted (in shares)		912		899	914		896
Cash dividends paid per share of common stock (in dollars per share)		$ 0.5425		$ 0.525	$ 1.0675		$ 1.0325
Alabama Power [Member]
Operating Revenues:
Retail revenues		$ 1,326		$ 1,249	$ 2,594		$ 2,546
Wholesale revenues, non-affiliates		57		65	123		150
Wholesale revenues, affiliates		20		68	35		137
Other revenues		52		55	104		112
Total operating revenues		1,455		1,437	2,856		2,945
Operating Expenses:
Fuel		343		414	653		846
Purchased power, non-affiliates		45		39	86		96
Purchased power, affiliates		49		37	103		86
Other operations and maintenance		370		330	768		655
Depreciation and amortization		160		172	318		347
Taxes other than income taxes		90		88	184		177
Total operating expenses		1,057		1,080	2,112		2,207
Operating Income (Loss)		398		357	744		738
Other Income and (Expense):
Allowance for equity funds used during construction		14		11	29		21
Interest expense, net of amounts capitalized		(69)		(63)	(134)		(125)
Other income (expense), net		(14)		(3)	(18)		(8)
Total other income and (expense)		(69)		(55)	(123)		(112)
Earnings Before Income Taxes		329		302	621		626
Income taxes (benefit)		122		119	235		246
Net Income (Loss)		207		183	386		380
Dividends on preferred and preference stock of subsidiaries		7		10	17		20
Net Income (Loss) After Dividends on Preferred and Preference Stock of Subsidiaries		200		173	369		360
Georgia Power [Member]
Operating Revenues:
Retail revenues		1,872		2,000	3,686		4,050
Wholesale revenues, non-affiliates		50		80	118		189
Wholesale revenues, affiliates		4		10	12		31
Other revenues		90		96	178		185
Total operating revenues		2,016		2,186	3,994		4,455
Operating Expenses:
Fuel		503		619	1,029		1,371
Purchased power, non-affiliates		78		63	138		142
Purchased power, affiliates		115		166	263		350
Other operations and maintenance		467		451	943		878
Depreciation and amortization		202		209	418		417
Taxes other than income taxes		97		106	195		209
Total operating expenses		1,462		1,614	2,986		3,367
Operating Income (Loss)		554		572	1,008		1,088
Other Income and (Expense):
Allowance for equity funds used during construction					10		16
Interest expense, net of amounts capitalized		(93)		(90)	(182)		(174)
Other income (expense), net		1		11	16		15
Total other income and (expense)		(92)		(79)	(166)		(159)
Earnings Before Income Taxes		462		493	842		929
Income taxes (benefit)		180		177	320		343
Net Income (Loss)		282		316	522		586
Dividends on preferred and preference stock of subsidiaries		5		5	9		9
Net Income (Loss) After Dividends on Preferred and Preference Stock of Subsidiaries		277		311	513		577
Gulf Power [Member]
Operating Revenues:
Retail revenues		327		310	620		613
Wholesale revenues, non-affiliates		27		34	52		70
Wholesale revenues, affiliates		13		24	35		76
Other revenues		17		16	34		32
Total operating revenues		384		384	741		791
Operating Expenses:
Fuel		122		145	232		314
Purchased power, non-affiliates		25		14	50		30
Purchased power, affiliates		9		9	17		16
Other operations and maintenance		91		82	185		164
Depreciation and amortization		40		39	60		71
Taxes other than income taxes		28		26	56		53
Total operating expenses		315		315	600		648
Operating Income (Loss)		69		69	141		143
Other Income and (Expense):
Allowance for equity funds used during construction		3		3	8		5
Interest expense, net of amounts capitalized		(12)		(13)	(26)		(27)
Other income (expense), net		(1)		(1)	(2)		(1)
Total other income and (expense)		(10)		(11)	(20)		(23)
Earnings Before Income Taxes		59		58	121		120
Income taxes (benefit)		21		22	44		45
Net Income (Loss)		38		36	77		75
Dividends on preferred and preference stock of subsidiaries		3		2	5		4
Net Income (Loss) After Dividends on Preferred and Preference Stock of Subsidiaries		35		34	72		71
Mississippi Power [Member]
Operating Revenues:
Retail revenues		189		211	357		418
Wholesale revenues, non-affiliates		63		75	141		172
Wholesale revenues, affiliates		18		20	45		43
Other revenues		5		5	9		9
Total operating revenues		275		311	552		642
Operating Expenses:
Fuel		115		143	229		290
Purchased power, non-affiliates		2		1	3		13
Purchased power, affiliates		2		6	4		15
Other operations and maintenance		68		61	144		125
Depreciation and amortization		30		24	57		47
Taxes other than income taxes		23		20	48		41
Estimated loss on Kemper IGCC		23		0	32		380
Total operating expenses		263		255	517		911
Operating Income (Loss)		12		56	35		(269)
Other Income and (Expense):
Allowance for equity funds used during construction		25		37	53		75
Interest expense, net of amounts capitalized		30		(13)	19		(25)
Other income (expense), net		(1)		(1)	(2)		(4)
Total other income and (expense)		54		23	70		46
Earnings Before Income Taxes		66		79	105		(223)
Income taxes (benefit)		16		16	20		(114)
Net Income (Loss)		50		63	85		(109)
Dividends on preferred and preference stock of subsidiaries		1		1	1		1
Net Income (Loss) After Dividends on Preferred and Preference Stock of Subsidiaries		49		62	84		(110)
Southern Power [Member]
Operating Revenues:
Wholesale revenues, non-affiliates		250		260	481		538
Wholesale revenues, affiliates		85		68	199		140
Other revenues		2		1	4		2
Total operating revenues		337		329	684		680
Operating Expenses:
Fuel		105		118	243		243
Purchased power, non-affiliates		18		17	34		45
Purchased power, affiliates		4		16	14		46
Other operations and maintenance		69		69	121		122
Depreciation and amortization		60		52	118		103
Taxes other than income taxes		6		6	12		11
Total operating expenses		262		278	542		570
Operating Income (Loss)		75		51	142		110
Other Income and (Expense):
Interest expense, net of amounts capitalized		(23)		(22)	(45)		(44)
Other income (expense), net		1		0	1		0
Total other income and (expense)		(22)		(22)	(44)		(44)
Earnings Before Income Taxes		53		29	98		66
Income taxes (benefit)		1		(3)	13		0
Net Income (Loss)		52		32	85		66
Less: Net income attributable to noncontrolling interests		6		1	6		2
Net income attributable to Southern Power Company		$ 46		$ 31	$ 79		$ 64
[1]	After dividends on preferred and preference stock of subsidiaries.
[2]	Segment net income (loss) for the traditional operating companies for the three months ended June 30, 2015 includes a $23 million pre-tax charge ($14 million after tax) for estimated probable losses on the Kemper IGCC. See Note (B) under "Integrated Coal Gasification Combined Cycle – Kemper IGCC Schedule and Cost Estimate" herein for additional information.
[3]	Segment net income (loss) for the traditional operating companies for the six months ended June 30, 2015 and June 30, 2014 includes a $32 million pre-tax charge ($20 million after tax) and a $380 million pre-tax charge ($235 million after tax), respectively, for estimated probable losses on the Kemper IGCC. See Note (B) under "Integrated Coal Gasification Combined Cycle – Kemper IGCC Schedule and Cost Estimate" herein for additional information.

Condensed Consolidated Stateme3

Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Pension and other post retirement benefit plans:
Total other comprehensive income (loss)			$ 7	$ 4
Southern Company [Member]
Net Income (loss)	$ 643	$ 628	1,169	996
Qualifying hedges:
Changes in fair value, net of tax	19	0	1	0
Reclassification adjustment for amounts included in net income, net of tax	2	1	3	2
Pension and other post retirement benefit plans:
Reclassification adjustment for amounts included in net income, net of tax	1	1	3	2
Total other comprehensive income (loss)	22	2	7	4
Dividends on preferred and preference stock of subsidiaries	(14)	(17)	(31)	(34)
Comprehensive Income (Loss)	651	613	1,145	966
Alabama Power [Member]
Net Income (loss)	207	183	386	380
Qualifying hedges:
Changes in fair value, net of tax	5	0	1	0
Reclassification adjustment for amounts included in net income, net of tax	0	0	1	1
Pension and other post retirement benefit plans:
Total other comprehensive income (loss)	5	0	2	1
Dividends on preferred and preference stock of subsidiaries	(7)	(10)	(17)	(20)
Comprehensive Income (Loss)	212	183	388	381
Georgia Power [Member]
Net Income (loss)	282	316	522	586
Qualifying hedges:
Changes in fair value, net of tax	14	0	0	0
Reclassification adjustment for amounts included in net income, net of tax	1	1	1	1
Pension and other post retirement benefit plans:
Total other comprehensive income (loss)	15	1	1	1
Dividends on preferred and preference stock of subsidiaries	(5)	(5)	(9)	(9)
Comprehensive Income (Loss)	297	317	523	587
Gulf Power [Member]
Net Income (loss)	38	36	77	75
Pension and other post retirement benefit plans:
Total other comprehensive income (loss)	0	0	0	0
Dividends on preferred and preference stock of subsidiaries	(3)	(2)	(5)	(4)
Comprehensive Income (Loss)	38	36	77	75
Mississippi Power [Member]
Net Income (loss)	50	63	85	(109)
Pension and other post retirement benefit plans:
Total other comprehensive income (loss)	0	0	0	0
Dividends on preferred and preference stock of subsidiaries	(1)	(1)	(1)	(1)
Comprehensive Income (Loss)	50	63	85	(109)
Southern Power [Member]
Net Income (loss)	52	32	85	66
Pension and other post retirement benefit plans:
Total other comprehensive income (loss)	0	0	0	0
Less: Comprehensive income attributable to noncontrolling interest/Dividends on preferred and preference stock of subsidiaries	6	1	6	2
Comprehensive Income (Loss)	$ 46	$ 31	$ 79	$ 64

Condensed Consolidated Stateme4

Condensed Consolidated Statements of Comprehensive Income (Unaudited) (Parenthetical) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Southern Company [Member]
Changes in fair value, tax	$ 12	$ 0	$ 1	$ 0
Reclassification adjustment for amounts of qualifying hedges included in net income, tax	1	0	2	2
Reclassification adjustment for amounts of pension and other post retirement benefit plans included in net income, tax	1	1	2	1
Alabama Power [Member]
Changes in fair value, tax	3	0	0	0
Reclassification adjustment for amounts of qualifying hedges included in net income, tax	0	0	1	0
Georgia Power [Member]
Changes in fair value, tax	9	0	0	0
Reclassification adjustment for amounts of qualifying hedges included in net income, tax	$ 0	$ 0	$ 1	$ 0

Condensed Consolidated Stateme5

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Southern Company [Member]
Operating Activities:
Net income (loss)	$ 1,169	$ 996
Adjustments to reconcile net income (loss) to net cash provided from operating activities —
Depreciation and amortization, total	1,171	1,182
Deferred income taxes	783	46
Allowance for equity funds used during construction	(102)	(119)
Stock based compensation expense	66	40
Estimated loss on Kemper IGCC	32	380
Income taxes receivable, non-current	(444)	0
Other, net	(6)	23
Changes in certain current assets and liabilities —
-Receivables	(158)	(579)
-Fossil fuel stock	136	419
-Materials and supplies	(21)	(20)
-Other current assets	(78)	(88)
-Accounts payable	(311)	(231)
-Accrued taxes	(60)	72
-Accrued compensation	(269)	(40)
-Mirror CWIP	82	67
-Other current liabilities	117	(78)
Net cash provided from operating activities	2,107	2,070
Investing Activities:
Property additions	(2,647)	(2,692)
Nuclear decommissioning trust fund purchases	(933)	(445)
Nuclear decommissioning trust fund sales	928	443
Cost of removal, net of salvage	(87)	(54)
Change in construction payables	56	89
Prepaid long-term service agreement	(110)	(93)
Other investing activities	27	(17)
Net cash used for investing activities	(2,766)	(2,769)
Financing Activities:
Increase (decrease) in notes payable, net	184	339
Proceeds —
Long-term debt issuances	3,075	1,314
Interest-bearing refundable deposit	0	75
Common stock issuances	116	318
Short-term borrowings	320	0
Redemptions and repurchases—
Long-term debt	(939)	(431)
Interest-bearing refundable deposits	(275)	0
Preferred and preference stock	(412)	0
Common stock	(115)	(5)
Short-term borrowings	(250)	0
Payment of common stock dividends	(972)	(920)
Payment of dividends on preferred and preference stock of subsidiaries	(36)	(34)
Other financing activities	66	(33)
Net cash provided from (used for) financing activities	762	623
Net Change in Cash and Cash Equivalents	103	(76)
Cash and Cash Equivalents at Beginning of Period	710	659
Cash and Cash Equivalents at End of Period	813	583
Cash paid (received) during the period for --
Interest (net of capitalized amounts)	374	365
Income taxes, net	(16)	212
Noncash transactions - Accrued property additions at end of period	345	509
Alabama Power [Member]
Operating Activities:
Net income (loss)	386	380
Adjustments to reconcile net income (loss) to net cash provided from operating activities —
Depreciation and amortization, total	387	416
Deferred income taxes	60	49
Allowance for equity funds used during construction	(29)	(21)
Other, net	(23)	(40)
Changes in certain current assets and liabilities —
-Receivables	(115)	(120)
-Fossil fuel stock	19	94
-Materials and supplies	3	(2)
-Other current assets	(55)	(57)
-Accounts payable	(212)	(94)
-Accrued taxes	177	104
-Accrued compensation	(66)	(17)
-Retail fuel cost over recovery - short-term	25	(23)
-Other current liabilities	40	5
Net cash provided from operating activities	597	674
Investing Activities:
Property additions	(612)	(637)
Nuclear decommissioning trust fund purchases	(278)	(121)
Nuclear decommissioning trust fund sales	278	121
Cost of removal, net of salvage	(28)	(30)
Change in construction payables	28	71
Other investing activities	(14)	(13)
Net cash used for investing activities	(626)	(609)
Financing Activities:
Increase (decrease) in notes payable, net	0	27
Proceeds —
Senior notes issuances	975	0
Capital contributions from parent company	10	12
Pollution control revenue bond	80	0
Redemptions and repurchases—
Preferred and preference stock	(412)	0
Pollution control revenue bond	(134)	0
Senior notes	(250)	0
Payment of preferred and preference stock dividends	(22)	(20)
Payment of common stock dividends	(286)	(275)
Other financing activities	(10)	1
Net cash provided from (used for) financing activities	(49)	(255)
Net Change in Cash and Cash Equivalents	(78)	(190)
Cash and Cash Equivalents at Beginning of Period	273	295
Cash and Cash Equivalents at End of Period	195	105
Cash paid (received) during the period for --
Interest (net of capitalized amounts)	118	114
Income taxes, net	47	141
Noncash transactions - Accrued property additions at end of period	35	89
Georgia Power [Member]
Operating Activities:
Net income (loss)	522	586
Adjustments to reconcile net income (loss) to net cash provided from operating activities —
Depreciation and amortization, total	512	503
Deferred income taxes	(6)	121
Allowance for equity funds used during construction	(10)	(16)
Retail fuel cost over recovery — long-term	0	(44)
Deferred expenses	28	31
Contract Amendment	(118)	0
Other, net	0	(12)
Changes in certain current assets and liabilities —
-Receivables	(21)	(353)
-Fossil fuel stock	101	255
-Prepaid income taxes	86	(7)
-Other current assets	(38)	(14)
-Accounts payable	(110)	(140)
-Accrued taxes	(125)	(65)
-Accrued compensation	(61)	(15)
-Retail fuel cost over recovery - short-term	0	(14)
-Other current liabilities	14	27
Net cash provided from operating activities	774	843
Investing Activities:
Property additions	(853)	(906)
Nuclear decommissioning trust fund purchases	(655)	(324)
Nuclear decommissioning trust fund sales	649	322
Change in construction payables, net of joint owner portion	26	52
Prepaid long-term service agreement	(40)	(47)
Other investing activities	(18)	(14)
Net cash used for investing activities	(891)	(917)
Financing Activities:
Increase (decrease) in notes payable, net	44	(359)
Proceeds —
Capital contributions from parent company	23	24
Pollution control revenue bond	170	0
FFB loan	600	1,000
Short-term borrowings	250	0
Redemptions and repurchases—
Pollution control revenue bond	(65)	(37)
Senior notes	(125)	0
Short-term borrowings	(250)	0
Payment of preferred and preference stock dividends	(9)	(9)
Payment of common stock dividends	(517)	(477)
FFB loan issuance costs	0	(49)
Other financing activities	(4)	(3)
Net cash provided from (used for) financing activities	117	90
Net Change in Cash and Cash Equivalents	0	16
Cash and Cash Equivalents at Beginning of Period	24	30
Cash and Cash Equivalents at End of Period	24	46
Cash paid (received) during the period for --
Interest (net of capitalized amounts)	170	157
Income taxes, net	240	145
Noncash transactions - Accrued property additions at end of period	171	267
Gulf Power [Member]
Operating Activities:
Net income (loss)	77	75
Adjustments to reconcile net income (loss) to net cash provided from operating activities —
Depreciation and amortization, total	64	75
Deferred income taxes	40	20
Allowance for equity funds used during construction	(8)	(5)
Other, net	11	1
Changes in certain current assets and liabilities —
-Receivables	(15)	(57)
-Fossil fuel stock	6	39
-Prepaid income taxes	12	9
-Other current assets	1	2
-Accounts payable	(9)	1
-Accrued taxes	15	12
-Accrued compensation	(10)	0
-Over recovered regulatory clause revenues	0	9
-Other current liabilities	(1)	(4)
Net cash provided from operating activities	183	177
Investing Activities:
Property additions	(148)	(159)
Cost of removal, net of salvage	(7)	(6)
Other investing activities	(19)	(5)
Net cash used for investing activities	(174)	(170)
Financing Activities:
Increase (decrease) in notes payable, net	4	3
Proceeds —
Common stock issuances	20	50
Pollution control revenue bond	0	42
Short-term borrowings	40	0
Redemptions and repurchases—
Pollution control revenue bond	0	(29)
Payment of preferred and preference stock dividends	(5)	(5)
Payment of common stock dividends	(65)	(62)
Other financing activities	2	2
Net cash provided from (used for) financing activities	(4)	1
Net Change in Cash and Cash Equivalents	5	8
Cash and Cash Equivalents at Beginning of Period	39	22
Cash and Cash Equivalents at End of Period	44	30
Cash paid (received) during the period for --
Interest (net of capitalized amounts)	26	26
Income taxes, net	(9)	17
Noncash transactions - Accrued property additions at end of period	28	31
Mississippi Power [Member]
Operating Activities:
Net income (loss)	85	(109)
Adjustments to reconcile net income (loss) to net cash provided from operating activities —
Depreciation and amortization, total	55	50
Deferred income taxes	694	(108)
Investment tax credits	32	28
Allowance for equity funds used during construction	(53)	(75)
Regulatory assets associated with Kemper IGCC	(50)	(26)
Estimated loss on Kemper IGCC	32	380
Income taxes receivable, non-current	(544)	0
Other, net	8	7
Changes in certain current assets and liabilities —
-Receivables	6	(32)
-Fossil fuel stock	5	32
-Prepaid income taxes	24	(12)
-Other current assets	(7)	(5)
-Accounts payable	(25)	4
-Accrued taxes	(51)	(23)
-Accrued interest	(7)	13
-Accrued compensation	(12)	4
-Over recovered regulatory clause revenues	32	(18)
-Mirror CWIP	82	67
-Other current liabilities	3	1
Net cash provided from operating activities	309	178
Investing Activities:
Property additions	(428)	(692)
Change in construction payables	(15)	(28)
Other investing activities	(17)	(13)
Net cash used for investing activities	(460)	(733)
Financing Activities:
Increase (decrease) in notes payable, net	475	0
Proceeds —
Capital contributions from parent company	77	211
Bonds — Other	0	12
Interest-bearing refundable deposit	0	75
Long-term debt issuance to parent company	0	220
Other long-term debt issuances	0	250
Short-term borrowings	30	0
Redemptions and repurchases—
Other long-term debt	(350)	0
Payment of preferred and preference stock dividends	(1)	(1)
Return of capital	0	(110)
Other financing activities	(1)	(1)
Net cash provided from (used for) financing activities	230	656
Net Change in Cash and Cash Equivalents	79	101
Cash and Cash Equivalents at Beginning of Period	133	145
Cash and Cash Equivalents at End of Period	212	246
Cash paid (received) during the period for --
Interest (net of capitalized amounts)	2	8
Income taxes, net	(181)	(34)
Noncash transactions - Accrued property additions at end of period	99	136
Issuance of promissory note to parent related to repayment of interest-bearing refundable deposit and accrued interest	301	0
Southern Power [Member]
Operating Activities:
Net income (loss)	85	66
Adjustments to reconcile net income (loss) to net cash provided from operating activities —
Depreciation and amortization, total	121	105
Deferred income taxes	59	(3)
Investment tax credits	153	26
Amortization of investment tax credits	(10)	(5)
Deferred revenues	(21)	(24)
Accrued income taxes, non-current	100	0
Other, net	10	7
Changes in certain current assets and liabilities —
-Receivables	(26)	(34)
-Fossil fuel stock	5	(1)
-Prepaid income taxes	(102)	21
-Other current assets	0	(1)
-Accounts payable	(31)	24
-Accrued taxes	(110)	7
-Other current liabilities	18	5
Net cash provided from operating activities	251	193
Investing Activities:
Plant acquisitions	(408)	(213)
Property additions	(154)	(11)
Change in construction payables	38	(3)
Payments pursuant to long-term service agreements	(45)	(23)
Other investing activities	(1)	(11)
Net cash used for investing activities	(570)	(261)
Financing Activities:
Increase (decrease) in notes payable, net	(195)	73
Proceeds —
Senior notes issuances	650	0
Redemptions and repurchases—
Distributions to noncontrolling interests	(1)	0
Contributions from noncontrolling interests	78	7
Payment of common stock dividends	(65)	(66)
Other financing activities	(3)	9
Net cash provided from (used for) financing activities	464	23
Net Change in Cash and Cash Equivalents	145	(45)
Cash and Cash Equivalents at Beginning of Period	75	69
Cash and Cash Equivalents at End of Period	220	24
Cash paid (received) during the period for --
Interest (net of capitalized amounts)	35	43
Income taxes, net	(72)	(59)
Noncash transactions - Accrued property additions at end of period	$ 38	$ 5

Condensed Consolidated Stateme6

Condensed Consolidated Statements of Cash Flows (Unaudited) (Parenthetical) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Southern Company [Member]
Net cash paid for capitalized interest	$ 57	$ 47
Alabama Power [Member]
Net cash paid for capitalized interest	10	8
Georgia Power [Member]
Net cash paid for capitalized interest	5	8
Gulf Power [Member]
Net cash paid for capitalized interest	3	2
Mississippi Power [Member]
Interest paid	39	37
Net cash paid for capitalized interest	37	29
Southern Power [Member]
Net cash paid for capitalized interest	$ 1	$ 0

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Millions	Jun. 30, 2015	Dec. 31, 2014
Deferred Charges and Other Assets:
Total Assets	$ 74,181	$ 70,923
Common Stockholders' Equity:
Total Stockholders' Equity	21,146	20,926
Southern Company [Member]
Current Assets:
Cash and cash equivalents	813	710
Receivables —
Customer accounts receivable	1,312	1,090
Unbilled revenues	579	432
Under recovered regulatory clause revenues	173	136
Other accounts and notes receivable	209	307
Accumulated provision for uncollectible accounts	(17)	(18)
Fossil fuel stock, at average cost	795	930
Materials and supplies, at average cost	1,043	1,039
Vacation pay	177	177
Prepaid expenses	564	665
Deferred income taxes, current	499	506
Other regulatory assets, current	382	346
Other current assets	76	50
Total current assets	6,605	6,370
Property, Plant, and Equipment:
In service	71,462	70,013
Less accumulated provision for depreciation	23,918	24,059
Plant in service, net of depreciation	47,544	45,954
Other utility plant, net	87	211
Nuclear fuel, at amortized cost	889	911
Construction work in progress	8,487	7,792
Total property, plant, and equipment	57,007	54,868
Other Property and Investments:
Nuclear decommissioning trusts, at fair value	1,572	1,546
Leveraged leases	751	743
Miscellaneous property and investments	232	203
Total other property and investments	2,555	2,492
Deferred Charges and Other Assets:
Deferred charges related to income taxes	1,533	1,510
Unamortized debt issuance expense	208	202
Unamortized loss on reacquired debt	234	243
Other regulatory assets, deferred	4,763	4,334
Income taxes receivable, non-current	444	0
Other deferred charges and assets	832	904
Total deferred charges and other assets	8,014	7,193
Total Assets	74,181	70,923
Current Liabilities:
Securities due within one year	3,643	3,333
Interest-bearing refundable deposits	0	275
Notes payable	1,057	803
Accounts payable —
Accounts payable	1,395	1,593
Customer deposits	398	390
Accrued taxes —
Accrued income taxes	12	151
Other accrued taxes	391	487
Accrued interest	241	295
Accrued vacation pay	222	223
Accrued compensation	305	576
Mirror CWIP	353	271
Other current liabilities	677	570
Total current liabilities	8,694	8,967
Long-term Debt:
Total Long-term Debt	22,674	20,841
Deferred Credits and Other Liabilities:
Accumulated deferred income taxes	12,187	11,568
Deferred credits related to income taxes	186	192
Accumulated deferred investment tax credits	1,290	1,208
Employee benefit obligations	2,375	2,432
Asset retirement obligations	2,860	2,168
Other cost of removal obligations	1,206	1,215
Other regulatory liabilities, deferred	408	398
Other deferred credits and liabilities	996	594
Total deferred credits and other liabilities	21,508	19,775
Total Liabilities	52,876	49,583
Redeemable Preferred Stock of Subsidiaries	118	375
Redeemable Noncontrolling Interest	41	39
Common Stockholders' Equity:
Common stock	4,555	4,539
Paid-in capital	6,123	5,955
Treasury, at cost	(142)	(26)
Retained earnings (accumulated deficit)	9,767	9,609
Accumulated other comprehensive income (loss)	(121)	(128)
Total common stockholders' equity	20,182	19,949
Preferred and Preference Stock of Subsidiaries	609	756
Noncontrolling Interest	355	221
Total Stockholders' Equity	21,146	20,926
Total Liabilities and Stockholders' Equity	74,181	70,923
Alabama Power [Member]
Current Assets:
Cash and cash equivalents	195	273
Receivables —
Customer accounts receivable	393	345
Unbilled revenues	170	138
Under recovered regulatory clause revenues	28	74
Other accounts and notes receivable	31	23
Affiliated companies	41	37
Accumulated provision for uncollectible accounts	(9)	(9)
Fossil fuel stock, at average cost	249	268
Materials and supplies, at average cost	415	406
Vacation pay	65	65
Prepaid expenses	168	244
Other regulatory assets, current	115	84
Other current assets	10	5
Total current assets	1,871	1,953
Property, Plant, and Equipment:
In service	23,812	23,080
Less accumulated provision for depreciation	8,565	8,522
Plant in service, net of depreciation	15,247	14,558
Nuclear fuel, at amortized cost	338	348
Construction work in progress	1,017	1,006
Total property, plant, and equipment	16,602	15,912
Other Property and Investments:
Equity investments in unconsolidated subsidiaries	68	66
Nuclear decommissioning trusts, at fair value	758	756
Miscellaneous property and investments	88	84
Total other property and investments	914	906
Deferred Charges and Other Assets:
Deferred charges related to income taxes	526	525
Deferred under recovered regulatory clause revenues	97	31
Other regulatory assets, deferred	1,054	1,063
Other deferred charges and assets	156	162
Total deferred charges and other assets	1,833	1,781
Total Assets	21,220	20,552
Current Liabilities:
Securities due within one year	600	454
Accounts payable —
Affiliated accounts payable	244	248
Other accounts payable	267	443
Customer deposits	88	87
Accrued taxes —
Accrued income taxes	3	2
Other accrued taxes	88	37
Accrued interest	75	66
Accrued vacation pay	54	54
Accrued compensation	66	131
Other current liabilities	105	82
Total current liabilities	1,590	1,604
Long-term Debt:
Total Long-term Debt	6,699	6,176
Deferred Credits and Other Liabilities:
Accumulated deferred income taxes	3,937	3,874
Deferred credits related to income taxes	71	72
Accumulated deferred investment tax credits	121	125
Employee benefit obligations	308	326
Asset retirement obligations	1,252	829
Other cost of removal obligations	742	744
Other regulatory liabilities, deferred	219	239
Deferred over recovered regulatory clause revenues	72	47
Other deferred credits and liabilities	79	79
Total deferred credits and other liabilities	6,801	6,335
Total Liabilities	15,090	14,115
Redeemable Preferred Stock	85	342
Preference Stock	196	343
Common Stockholders' Equity:
Common stock	1,222	1,222
Paid-in capital	2,324	2,304
Retained earnings (accumulated deficit)	2,331	2,255
Accumulated other comprehensive income (loss)	(28)	(29)
Total common stockholders' equity	5,849	5,752
Total Liabilities and Stockholders' Equity	21,220	20,552
Georgia Power [Member]
Current Assets:
Cash and cash equivalents	24	24
Receivables —
Customer accounts receivable	778	553
Unbilled revenues	294	201
Joint owner accounts receivable	44	121
Other accounts and notes receivable	46	61
Affiliated companies	20	18
Accumulated provision for uncollectible accounts	(6)	(6)
Fossil fuel stock, at average cost	338	439
Materials and supplies, at average cost	425	438
Vacation pay	91	91
Prepaid income taxes	225	278
Other regulatory assets, current	147	136
Other current assets	86	74
Total current assets	2,512	2,428
Property, Plant, and Equipment:
In service	31,363	31,083
Less accumulated provision for depreciation	10,961	11,222
Plant in service, net of depreciation	20,402	19,861
Other utility plant, net	10	211
Nuclear fuel, at amortized cost	551	563
Construction work in progress	4,171	4,031
Total property, plant, and equipment	25,134	24,666
Other Property and Investments:
Equity investments in unconsolidated subsidiaries	61	58
Nuclear decommissioning trusts, at fair value	814	789
Miscellaneous property and investments	37	38
Total other property and investments	912	885
Deferred Charges and Other Assets:
Deferred charges related to income taxes	681	698
Deferred under recovered regulatory clause revenues	0	197
Other regulatory assets, deferred	2,063	1,753
Other deferred charges and assets	446	403
Total deferred charges and other assets	3,190	3,051
Total Assets	31,748	31,030
Current Liabilities:
Securities due within one year	1,660	1,154
Notes payable	200	156
Accounts payable —
Affiliated accounts payable	392	451
Other accounts payable	574	555
Customer deposits	259	253
Accrued taxes —
Other accrued taxes	207	332
Accrued interest	96	96
Accrued vacation pay	62	63
Accrued compensation	81	153
Other current liabilities	309	257
Total current liabilities	3,840	3,470
Long-term Debt:
Total Long-term Debt	8,914	8,683
Deferred Credits and Other Liabilities:
Accumulated deferred income taxes	5,524	5,507
Deferred credits related to income taxes	103	106
Accumulated deferred investment tax credits	191	196
Employee benefit obligations	870	903
Asset retirement obligations	1,301	1,223
Other deferred credits and liabilities	286	255
Total deferred credits and other liabilities	8,275	8,190
Total Liabilities	21,029	20,343
Redeemable Preferred Stock	45	45
Preference Stock	221	221
Common Stockholders' Equity:
Common stock	398	398
Paid-in capital	6,232	6,196
Retained earnings (accumulated deficit)	3,830	3,835
Accumulated other comprehensive income (loss)	(7)	(8)
Total common stockholders' equity	10,453	10,421
Total Liabilities and Stockholders' Equity	31,748	31,030
Gulf Power [Member]
Current Assets:
Cash and cash equivalents	44	39
Receivables —
Customer accounts receivable	93	73
Unbilled revenues	77	58
Under recovered regulatory clause revenues	38	57
Other accounts and notes receivable	9	8
Affiliated companies	4	10
Accumulated provision for uncollectible accounts	(2)	(2)
Fossil fuel stock, at average cost	95	101
Materials and supplies, at average cost	55	56
Prepaid expenses	35	40
Other regulatory assets, current	72	74
Other current assets	3	2
Total current assets	523	516
Property, Plant, and Equipment:
In service	4,600	4,495
Less accumulated provision for depreciation	1,234	1,296
Plant in service, net of depreciation	3,366	3,199
Other utility plant, net	77	0
Construction work in progress	387	465
Total property, plant, and equipment	3,830	3,664
Other Property and Investments:
Total other property and investments	15	15
Deferred Charges and Other Assets:
Deferred charges related to income taxes	59	56
Other regulatory assets, deferred	406	416
Other deferred charges and assets	41	41
Total deferred charges and other assets	506	513
Total Assets	4,874	4,708
Current Liabilities:
Notes payable	154	110
Accounts payable —
Affiliated accounts payable	72	87
Other accounts payable	52	56
Customer deposits	36	35
Accrued taxes —
Other accrued taxes	24	9
Accrued interest	10	11
Accrued compensation	13	23
Deferred capacity expense, current	22	22
Liabilities from risk management activities	32	37
Other current liabilities	21	23
Total current liabilities	436	413
Long-term Debt:
Total Long-term Debt	1,370	1,370
Deferred Credits and Other Liabilities:
Accumulated deferred income taxes	852	800
Employee benefit obligations	119	121
Other cost of removal obligations	222	235
Other regulatory liabilities, deferred	49	49
Deferred capacity expense	152	163
Other deferred credits and liabilities	187	101
Total deferred credits and other liabilities	1,581	1,469
Total Liabilities	3,387	3,252
Preference Stock	147	147
Common Stockholders' Equity:
Common stock	503	483
Paid-in capital	564	560
Retained earnings (accumulated deficit)	274	267
Accumulated other comprehensive income (loss)	(1)	(1)
Total common stockholders' equity	1,340	1,309
Total Liabilities and Stockholders' Equity	4,874	4,708
Mississippi Power [Member]
Current Assets:
Cash and cash equivalents	212	133
Receivables —
Customer accounts receivable	44	43
Unbilled revenues	37	35
Other accounts and notes receivable	11	11
Affiliated companies	43	51
Accumulated provision for uncollectible accounts	(1)	(1)
Fossil fuel stock, at average cost	95	100
Materials and supplies, at average cost	69	62
Prepaid income taxes	193	191
Other regulatory assets, current	69	73
Other current assets	7	6
Total current assets	779	704
Property, Plant, and Equipment:
In service	4,456	4,378
Less accumulated provision for depreciation	1,194	1,173
Plant in service, net of depreciation	3,262	3,205
Construction work in progress	2,543	2,161
Total property, plant, and equipment	5,805	5,366
Other Property and Investments:
Total other property and investments	6	5
Deferred Charges and Other Assets:
Deferred charges related to income taxes	260	226
Other regulatory assets, deferred	482	385
Income taxes receivable, non-current	544	0
Other deferred charges and assets	71	71
Total deferred charges and other assets	1,357	682
Total Assets	7,947	6,757
Current Liabilities:
Securities due within one year	429	778
Interest-bearing refundable deposits	0	275
Notes payable	505	0
Accounts payable —
Affiliated accounts payable	88	86
Other accounts payable	136	178
Accrued taxes —
Accrued income taxes	0	142
Other accrued taxes	47	84
Accrued interest	13	76
Accrued compensation	14	26
Over recovered regulatory clause liabilities	33	1
Mirror CWIP	353	271
Other current liabilities	59	61
Total current liabilities	1,677	1,978
Long-term Debt:
Long-term debt, affiliated	301	0
Long-term debt, non-affiliated	1,623	1,630
Total Long-term Debt	1,924	1,630
Deferred Credits and Other Liabilities:
Accumulated deferred income taxes	844	285
Accumulated deferred investment tax credits	282	283
Employee benefit obligations	146	148
Asset retirement obligations	148	48
Other cost of removal obligations	170	166
Other regulatory liabilities, deferred	65	64
Other deferred credits and liabilities	410	38
Total deferred credits and other liabilities	2,065	1,032
Total Liabilities	5,666	4,640
Redeemable Preferred Stock	33	33
Common Stockholders' Equity:
Common stock	38	38
Paid-in capital	2,692	2,612
Retained earnings (accumulated deficit)	(475)	(559)
Accumulated other comprehensive income (loss)	(7)	(7)
Total common stockholders' equity	2,248	2,084
Total Liabilities and Stockholders' Equity	7,947	6,757
Southern Power [Member]
Current Assets:
Cash and cash equivalents	220	75
Receivables —
Customer accounts receivable	106	77
Other accounts and notes receivable	11	15
Affiliated companies	40	34
Fossil fuel stock, at average cost	17	22
Materials and supplies, at average cost	59	58
Prepaid income taxes	122	19
Deferred income taxes, current	144	306
Other current assets	16	21
Total current assets	735	627
Property, Plant, and Equipment:
In service	6,047	5,657
Less accumulated provision for depreciation	1,125	1,035
Plant in service, net of depreciation	4,922	4,622
Construction work in progress	201	11
Total property, plant, and equipment	5,123	4,633
Other Property and Investments:
Goodwill	2	2
Other intangible assets, net of amortization of $10 and $8 at June 30, 2015 and December 31, 2014, respectively	69	47
Total other property and investments	71	49
Deferred Charges and Other Assets:
Prepaid long-term service agreements	141	124
Other deferred charges and assets -- affiliated	13	5
Other deferred charges and assets	143	112
Total deferred charges and other assets	297	241
Total Assets	6,226	5,550
Current Liabilities:
Securities due within one year	525	525
Notes payable	8	195
Accounts payable —
Affiliated accounts payable	65	78
Other accounts payable	55	30
Accrued taxes —
Accrued income taxes	7	72
Accrued interest	31	30
Other current liabilities	53	17
Total current liabilities	744	947
Long-term Debt:
Total Long-term Debt	1,737	1,095
Deferred Credits and Other Liabilities:
Accumulated deferred income taxes	760	863
Accumulated deferred investment tax credits	693	601
Accrued income taxes, non-current	100	0
Deferred capacity revenues -- affiliated	9	15
Other deferred credits and liabilities — affiliated	0	1
Other deferred credits and liabilities	22	18
Total deferred credits and other liabilities	1,584	1,498
Total Liabilities	4,065	3,540
Redeemable Noncontrolling Interest	41	39
Common Stockholders' Equity:
Common stock	0	0
Paid-in capital	1,176	1,176
Retained earnings (accumulated deficit)	587	573
Accumulated other comprehensive income (loss)	4	3
Total common stockholders' equity	1,767	1,752
Noncontrolling Interest, Total	353	219
Total Stockholders' Equity	2,120	1,971
Total Liabilities and Stockholders' Equity	$ 6,226	$ 5,550

Condensed Consolidated Balance8

Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($) $ in Millions	Jun. 30, 2015	Dec. 31, 2014
Southern Company [Member]
Common stock, par value (in dollars per share)	$ 5	$ 5
Common stock, shares authorized	1,500,000,000	1,500,000,000
Common stock, shares issued	912,000,000	909,000,000
Treasury shares at cost	3,300,000	700,000
Alabama Power [Member]
Common stock, par value (in dollars per share)	$ 40	$ 40
Common stock, shares authorized	40,000,000	40,000,000
Common stock, shares outstanding	30,537,500	30,537,500
Georgia Power [Member]
Common stock, no par value (in dollars per share)	$ 0	$ 0
Common stock, shares authorized	20,000,000	20,000,000
Common stock, shares outstanding	9,261,500	9,261,500
Gulf Power [Member]
Common stock, no par value (in dollars per share)	$ 0	$ 0
Common stock, shares authorized	20,000,000	20,000,000
Common stock, shares outstanding	5,642,717	5,442,717
Mississippi Power [Member]
Common stock, no par value (in dollars per share)	$ 0	$ 0
Common stock, shares authorized	1,130,000	1,130,000
Common stock, shares outstanding	1,121,000	1,121,000
Southern Power [Member]
Other intangible assets, accumulated amortization	$ 10	$ 8
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	1,000,000	1,000,000
Common stock, shares outstanding	1,000	1,000

Introduction

Introduction	6 Months Ended
	Jun. 30, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
INTRODUCTION	INTRODUCTION The condensed quarterly financial statements of each registrant included herein have been prepared by such registrant, without audit, pursuant to the rules and regulations of the SEC. The Condensed Balance Sheets as of December 31, 2014 have been derived from the audited financial statements of each registrant. In the opinion of each registrant's management, the information regarding such registrant furnished herein reflects all adjustments, which, except as otherwise disclosed, are of a normal recurring nature, necessary to present fairly the results of operations for the periods ended June 30, 2015 and 2014 . Certain information and footnote disclosures normally included in annual financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations, although each registrant believes that the disclosures regarding such registrant are adequate to make the information presented not misleading. Disclosures which would substantially duplicate the disclosures in the Form 10-K and details which have not changed significantly in amount or composition since the filing of the Form 10-K are generally omitted from this Quarterly Report on Form 10-Q unless specifically required by GAAP. Therefore, these Condensed Financial Statements should be read in conjunction with the financial statements and the notes thereto included in the Form 10-K. Due to the seasonal variations in the demand for energy, operating results for the periods presented are not necessarily indicative of the operating results to be expected for the full year. Certain prior year data presented in the financial statements have been reclassified to conform to the current year presentation. These reclassifications had no impact on the results of operations, financial position, or cash flows of any registrant. On February 6, 2015, Gulf Power announced plans to retire its coal-fired generation at Plant Smith Units 1 and 2 ( 357 MWs) by March 31, 2016. In March 2015, in connection with this retirement, Gulf Power reclassified the net carrying value of these units from plant in service, net of depreciation, to other utility plant, net. Gulf Power expects to recover through its rates the remaining book value of the retired units and certain costs associated with the retirements; however, recovery will be considered by the Florida PSC in future rate proceedings . In June 2015, Georgia Power identified an error affecting the billing to a small number of large commercial and industrial customers under a rate plan allowing for variable demand-driven pricing from January 1, 2013 to June 30, 2015. In the second quarter 2015, Georgia Power recorded an out of period adjustment of approximately $75 million to decrease retail revenues, resulting in a decrease to net income of approximately $47 million . Georgia Power evaluated the effects of this error on the interim and annual periods that included the billing error, as well as the current period. Based on an analysis of qualitative and quantitative factors, Georgia Power determined the error was not material to any affected period and, therefore, an amendment of previously filed financial statements was not required. Recently Issued Accounting Standards The Financial Accounting Standards Board's (FASB) ASC 606, Revenue from Contracts with Customers , revises the accounting for revenue recognition effective for fiscal years beginning after December 15, 2017. The registrants continue to evaluate the requirements of ASC 606. The ultimate impact of the new standard has not yet been determined. On February 18, 2015, the FASB issued Accounting Standards Update (ASU) 2015-02, Amendments to the Consolidation Analysis , which makes certain changes to both the variable interest model and the voting model, including changes to the identification of variable interests, the variable interest entity characteristics for a limited partnership or similar entity, and the primary beneficiary determination. This ASU is effective for fiscal years beginning after December 15, 2015. Southern Power is currently evaluating these requirements. The ultimate impact of this ASU on Southern Power has not yet been determined. On April 7, 2015, the FASB issued ASU No. 2015-03, Interest – Imputation of Interest (Subtopic 835-30): Simplifying the Presentation of Debt Issuance Costs . The ASU requires that debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability and is effective for fiscal years beginning after December 15, 2015. Southern Company currently reflects unamortized debt issuance costs in unamortized debt issuance expense on its balance sheet. The traditional operating companies and Southern Power currently reflect unamortized debt issuance costs in other deferred charges and assets on their balance sheets. Upon adoption, the reclassification will not have a material impact on the results of operations, financial position, or cash flows of any registrant. Asset Retirement Obligations See Note 1 to the financial statements of Southern Company, Alabama Power, Georgia Power, Gulf Power, and Mississippi Power under "Asset Retirement Obligations and Other Costs of Removal" in Item 8 of the Form 10-K for additional information regarding the EPA's regulation of CCR. On April 17, 2015, the EPA published the Disposal of Coal Combustion Residuals from Electric Utilities final rule (CCR Rule) in the Federal Register, setting October 19, 2015 as the effective date of the CCR Rule. Therefore, Alabama Power, Gulf Power, and Mississippi Power recorded new asset retirement obligations (ARO) for facilities that are subject to the CCR Rule. Georgia Power had previously recorded AROs as a result of state requirements in Georgia which closely align with the requirements of the CCR Rule. The cost estimates are based on information that was known as of June 30, 2015 using various assumptions related to closure and post-closure costs, timing of future cash outlays, inflation and discount rates, and the potential methods for complying with the CCR Rule requirements. As further analysis is performed, including evaluation of the expected timing and method of compliance and refinement of assumptions underlying the cost estimates, such as the quantities of CCR at each site, the traditional operating companies expect to periodically update these estimates. As of June 30, 2015 , details of the AROs, including those related to the CCR Rule, included in Southern Company's and the traditional operating companies' Condensed Balance Sheets herein were as follows: Southern Company Alabama Power Georgia Power Gulf Power Mississippi Power (in millions) Balance at beginning of year $ 2,201 $ 829 $ 1,255 $ 17 $ 48 Liabilities incurred 612 401 — 71 97 Liabilities settled (10 ) (1 ) (9 ) — — Accretion 53 23 28 — 1 Cash flow revisions 58 — 82 4 2 Balance at end of period $ 2,914 $ 1,252 $ 1,356 $ 92 $ 148 The increases in liabilities incurred and cash flow revisions for the six months ended June 30, 2015 primarily relate to an increase in AROs associated with facilities impacted by the CCR Rule. In connection with a proposed settlement related to the closure of Plant Scholz, Gulf Power may incur additional AROs associated with CCR of approximately $15 million to $35 million .

Contingencies and Regulatory Ma

Contingencies and Regulatory Matters	6 Months Ended
	Jun. 30, 2015
Commitments and Contingencies Disclosure [Abstract]
CONTINGENCIES AND REGULATORY MATTERS	CONTINGENCIES AND REGULATORY MATTERS See Note 3 to the financial statements of the registrants in Item 8 of the Form 10-K for information relating to various lawsuits, other contingencies, and regulatory matters. General Litigation Matters Each registrant is subject to certain claims and legal actions arising in the ordinary course of business. In addition, business activities of Southern Company's subsidiaries are subject to extensive governmental regulation related to public health and the environment, such as regulation of air emissions and water discharges. Litigation over environmental issues and claims of various types, including property damage, personal injury, common law nuisance, and citizen enforcement of environmental requirements such as air quality and water standards, has occurred throughout the U.S. This litigation has included claims for damages alleged to have been caused by CO 2 and other emissions, CCR, and alleged exposure to hazardous materials, and/or requests for injunctive relief in connection with such matters. The ultimate outcome of such pending or potential litigation against each registrant and any subsidiaries cannot be predicted at this time; however, for current proceedings not specifically reported herein or in Note 3 to the financial statements of each registrant in Item 8 of the Form 10-K, management does not anticipate that the ultimate liabilities, if any, arising from such current proceedings would have a material effect on such registrant's financial statements. Environmental Matters New Source Review Actions As part of a nationwide enforcement initiative against the electric utility industry which began in 1999, the EPA brought civil enforcement actions in federal district court against Alabama Power and Georgia Power alleging violations of the New Source Review (NSR) provisions of the Clean Air Act at certain coal-fired electric generating units, including units co-owned by Gulf Power and Mississippi Power. These civil actions sought penalties and injunctive relief, including orders requiring installation of the best available control technologies at the affected units. The case against Georgia Power (including claims related to a unit co-owned by Gulf Power) has been administratively closed in the U.S. District Court for the Northern District of Georgia since 2001. The case against Alabama Power (including claims involving a unit co-owned by Mississippi Power) was partially settled in 2006 through a consent decree with the EPA, and additional claims remain pending in the U.S. District Court for the Northern District of Alabama. On June 25, 2015, the U.S. Department of Justice filed a joint stipulation between Alabama Power, the EPA, and the U.S. Department of Justice proposing to modify the 2006 consent decree to resolve all remaining claims for relief alleged in the case against Alabama Power. If approved by the U.S. District Court for the Northern District of Alabama, Alabama Power will, without admitting liability, operate subject to emission rates and a cap on certain units and requirements to use only natural gas at certain units, including a unit co-owned by Mississippi Power; retire certain units at Plants Gorgas and Barry; pay a $100,000 civil penalty; and invest $1.5 million in electric transportation infrastructure projects over three years. The ultimate outcome of these matters cannot be determined at this time. Environmental Remediation The Southern Company system must comply with environmental laws and regulations that cover the handling and disposal of waste and releases of hazardous substances. Under these various laws and regulations, the Southern Company system could incur substantial costs to clean up properties. The traditional operating companies have each received authority from their respective state PSCs to recover approved environmental compliance costs through regulatory mechanisms. These rates are adjusted annually or as necessary within limits approved by the state PSCs. Georgia Power's environmental remediation liability as of June 30, 2015 was $40 million . Georgia Power has been designated or identified as a potentially responsible party (PRP) at sites governed by the Georgia Hazardous Site Response Act and/or by the federal Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), including a site in Brunswick, Georgia on the CERCLA National Priorities List. The parties have completed the removal of wastes from the Brunswick site as ordered by the EPA. Additional cleanup and claims for recovery of natural resource damages at this site or for the assessment and potential cleanup of other sites are anticipated. Georgia Power and numerous other entities have been designated by the EPA as PRPs at the Ward Transformer Superfund site located in Raleigh, North Carolina. In 2011, the EPA issued a Unilateral Administrative Order (UAO) to Georgia Power and 22 other parties, ordering specific remedial action of certain areas at the site. Later in 2011, Georgia Power filed a response with the EPA stating it has sufficient cause to believe it is not a liable party under CERCLA. The EPA notified Georgia Power in 2011 that it is considering enforcement options against Georgia Power and other non-complying UAO recipients. If the EPA pursues enforcement actions and the court determines that a respondent failed to comply with the UAO without sufficient cause, the EPA may also seek civil penalties of up to $37,500 per day for the violation and punitive damages of up to three times the costs incurred by the EPA as a result of the party's failure to comply with the UAO. In addition to the EPA's action at this site, Georgia Power, along with many other parties, was sued in a private action by several existing PRPs for cost recovery related to the removal action. In 2013, the U.S. District Court for the Eastern District of North Carolina Western Division ruled that Georgia Power has no liability in the private action and, on March 20, 2015, the U.S. Court of Appeals for the Fourth Circuit affirmed the lower court's ruling. Therefore, the private action is now concluded. The ultimate outcome of these remaining matters will depend upon the success of defenses asserted, the ultimate number of PRPs participating in the cleanup, and numerous other factors and cannot be determined at this time; however, as a result of Georgia Power's regulatory treatment for environmental remediation expenses, these matters are not expected to have a material impact on Southern Company's or Georgia Power's financial statements. See Note 1 to the financial statements of Georgia Power under "Environmental Remediation Recovery" in Item 8 of the Form 10-K for additional information regarding the regulatory treatment. Gulf Power's environmental remediation liability includes estimated costs of environmental remediation projects of approximately $47 million as of June 30, 2015 . These estimated costs primarily relate to site closure criteria by the Florida Department of Environmental Protection (FDEP) for potential impacts to soil and groundwater from herbicide applications at Gulf Power substations. The schedule for completion of the remediation projects is subject to FDEP approval. The projects have been approved by the Florida PSC for recovery through Gulf Power's environmental cost recovery clause; therefore, these liabilities have no impact on net income. In 2003, Mississippi Power and numerous other entities were designated by the Texas Commission on Environmental Quality (TCEQ) as PRPs at a site that was owned by an electric transformer company that handled Mississippi Power's transformers. The TCEQ approved the final site remediation plan in 2013 and, in March 2014, the impacted utilities, including Mississippi Power, agreed to commence remediation actions on the site. Mississippi Power's environmental remediation liability was $0.3 million as of June 30, 2015 and is expected to be recovered through the ECO Plan. The final outcome of these matters cannot be determined at this time. However, based on the currently known conditions at these sites and the nature and extent of activities relating to these sites, management of Southern Company, Georgia Power, Gulf Power, and Mississippi Power does not believe that additional liabilities, if any, at these sites would be material to their respective financial statements . Nuclear Fuel Disposal Cost Litigation Acting through the DOE and pursuant to the Nuclear Waste Policy Act of 1982, the U.S. government entered into contracts with Alabama Power and Georgia Power that require the DOE to dispose of spent nuclear fuel and high level radioactive waste generated at Plants Hatch and Farley and Plant Vogtle Units 1 and 2 beginning no later than January 31, 1998. The DOE has yet to commence the performance of its contractual and statutory obligation to dispose of spent nuclear fuel. Consequently, Alabama Power and Georgia Power pursued and continue to pursue legal remedies against the U.S. government for its partial breach of contract. In December 2014, the Court of Federal Claims entered a judgment in favor of Georgia Power and Alabama Power in the second spent nuclear fuel lawsuit seeking damages for the period from January 1, 2005 through December 31, 2010. Georgia Power recovered approximately $18 million , based on its ownership interests, and Alabama Power recovered approximately $26 million . The judgment amounts were paid on March 19, 2015. In March 2015, Georgia Power credited the award to accounts where the original costs were charged and reduced rate base, fuel, and cost of service for the benefit of customers. The final outcome of this matter for Alabama Power cannot be determined at this time; however, no material impact on Southern Company's or Alabama Power's net income is expected as the damage amounts collected from the government are expected to be used for the benefit of customers. In March 2014, Alabama Power and Georgia Power filed additional lawsuits against the U.S. government for the costs of continuing to store spent nuclear fuel at Plants Farley and Hatch and Plant Vogtle Units 1 and 2 for the period from January 1, 2011 through December 31, 2013. The damage period was subsequently extended to December 31, 2014. Damages will continue to accumulate until the issue is resolved or storage is provided. No amounts have been recognized in the financial statements as of June 30, 2015 for any potential recoveries from the additional lawsuits. The final outcome of these matters cannot be determined at this time; however, no material impact on Southern Company's, Alabama Power's, or Georgia Power's net income is expected. FERC Matters Municipal and Rural Associations Tariff See Note 3 to the financial statements of Mississippi Power under "FERC Matters" in Item 8 of the Form 10-K for additional information regarding a settlement agreement entered into by Mississippi Power regarding the establishment of a regulatory asset for Kemper IGCC-related costs. See Note 3 to the financial statements of Southern Company and Mississippi Power under "Integrated Coal Gasification Combined Cycle" in Item 8 of the Form 10-K and "Integrated Coal Gasification Combined Cycle" herein for information regarding Mississippi Power's construction of the Kemper IGCC. On March 31, 2015, Mississippi Power reached a settlement agreement with its wholesale customers and filed a request with the FERC to forgo the Municipal and Rural Associations cost-based electric tariff increase reflected in the filing by, among other things, increasing the accrual of AFUDC in lieu of including CWIP in rate base. The settlement agreement, which was accepted by the FERC on May 13, 2015, provides that the additional accrual of AFUDC was effective April 1, 2015. The additional resulting AFUDC is projected to be approximately $11 million annually, of which $8 million relates to the Kemper IGCC. In addition, a settlement agreement entered into in 2014 and approved by the FERC allowed for an adjustment to the wholesale revenue requirement in the event the Kemper IGCC, or any substantial portion thereof, was placed in service before or after December 1, 2014. A regulatory asset account was recorded as a result of a portion of the Kemper IGCC being placed in service prior to the projected date. The March 31, 2015 settlement agreement provides that the regulatory asset will be amortized over nine months, beginning April 1, 2015. Market-Based Rate Authority The traditional operating companies and Southern Power have authority from the FERC to sell electricity at market-based rates. Since 2008, that authority, for certain balancing authority areas, has been conditioned on compliance with the requirements of an energy auction, which the FERC found to be tailored mitigation that addresses potential market power concerns. In accordance with FERC regulations governing such authority, the traditional operating companies and Southern Power filed a triennial market power analysis on June 30, 2014, which included continued reliance on the energy auction as tailored mitigation. On April 27, 2015, the FERC issued an order finding that the traditional operating companies' and Southern Power's existing tailored mitigation may not effectively mitigate the potential to exert market power in certain areas served by the traditional operating companies and in some adjacent areas. To retain market-based rate authority, the FERC directed the traditional operating companies and Southern Power to show why market-based rate authority should not be revoked in these areas or to provide a mitigation plan to further address market power concerns. The traditional operating companies and Southern Power filed a request for rehearing on May 27, 2015 and on June 26, 2015 filed their response with the FERC. The ultimate outcome of this matter cannot be determined at this time. Retail Regulatory Matters Alabama Power See Note 3 to the financial statements of Southern Company and Alabama Power under "Retail Regulatory Matters – Alabama Power" and "Retail Regulatory Matters," respectively, in Item 8 of the Form 10-K for additional information regarding Alabama Power's recovery of retail costs through various regulatory clauses and accounting orders. The recovery balance of each regulatory clause follows: Regulatory Clause Balance Sheet Line Item June 30, 2015 December 31, 2014 (in millions) Rate CNP Compliance – Under * Deferred under recovered regulatory clause revenues $ 25 $ 2 Under recovered regulatory clause revenues, current 29 47 Rate CNP PPA – Under Deferred under recovered regulatory clause revenues 72 29 Under recovered regulatory clause revenues, current — 27 Retail Energy Cost Recovery – Over Deferred over recovered regulatory clause revenues 72 47 Natural Disaster Reserve Other regulatory liabilities, deferred 81 84 * Formerly Known As Rate CNP Environmental Rate CNP See Note 3 to the financial statements of Southern Company under "Retail Regulatory Matters – Alabama Power – Rate CNP" and " – Non-Environmental Federal Mandated Costs Accounting Order" and of Alabama Power under "Retail Regulatory Matters – Rate CNP" and " – Non-Environmental Federal Mandated Costs Accounting Order" in Item 8 of the Form 10-K for additional information regarding Alabama Power's development of a revised cost recovery mechanism and the normal purchases and normal sales (NPNS) exception for wind PPAs. On March 3, 2015, the Alabama PSC approved a modification to Rate CNP Environmental to include compliance costs for both environmental and non-environmental mandates. The recoverable non-environmental compliance costs result from laws, regulations, and other mandates directed at the utility industry involving the security, reliability, safety, sustainability, or similar considerations impacting Alabama Power's facilities or operations. This modification to Rate CNP Environmental was effective March 20, 2015 with the revised rate now defined as Rate CNP Compliance. Alabama Power incurred $30 million of non-environmental compliance costs during the first six months of 2015 and will be limited to recovery of $50 million for the year. Customer rates will not be impacted before January 2016; therefore, the modification will increase the under recovered position for Rate CNP Compliance during 2015. In April 2015, the FASB proposed new accounting guidance to allow the NPNS exception for physical forward transactions in nodal energy markets, consistent with the manner in which Alabama Power currently accounts for its two wind PPAs. On July 9, 2015, the FASB ratified the consensus reached by the Emerging Issues Task Force to allow the exception in such cases and voted to issue a final accounting standard. Environmental Accounting Order In April 2015, as part of its environmental compliance strategy, Alabama Power retired Plant Gorgas Units 6 and 7. These units represented 200 MWs of Alabama Power's approximately 12,200 MWs of generating capacity. Additionally, in April 2015, Alabama Power ceased using coal at Plant Barry Units 1 and 2 ( 250 MWs), but such units will remain available on a limited basis with natural gas as the fuel source. No later than April 2016, Alabama Power expects to cease using coal at Plant Greene County Units 1 and 2 ( 300 MWs) and begin operating those units solely on natural gas. Subject to the final approval of the New Source Review stipulation, Alabama Power will also retire Plant Barry Unit 3 ( 225 MWs) which is currently unavailable for generation. See "Environmental Matters – New Source Review Actions" herein for additional information regarding the NSR actions. In accordance with an accounting order from the Alabama PSC, Alabama Power transferred the unrecovered plant asset balances to a regulatory asset at their respective retirement dates. The regulatory asset will be amortized over the remaining useful lives, as established prior to the decision for retirement. As a result, these decisions will not have a significant impact on Southern Company's or Alabama Power's financial statements. Georgia Power Integrated Resource Plan See Note 3 to the financial statements of Southern Company and Georgia Power under "Retail Regulatory Matters – Georgia Power – Integrated Resource Plans" and "Retail Regulatory Matters – Integrated Resource Plans," respectively, in Item 8 of the Form 10-K for additional information. To comply with the April 16, 2015 effective date of the MATS rule, Plant Branch Units 1, 3, and 4 ( 1,266 MWs), Plant Yates Units 1 through 5 ( 579 MWs), and Plant McManus Units 1 and 2 ( 122 MWs) were retired on April 15, 2015. In addition, operations were discontinued at Plant Mitchell Unit 3 ( 155 MWs) and its decertification will be requested in connection with the triennial Integrated Resource Plan in 2016. The switch to natural gas as the primary fuel is complete at Plant Yates Units 7 and 6 and the units were returned to service on May 4, 2015 and June 27, 2015, respectively. Fuel Cost Recovery See Note 3 to the financial statements of Southern Company and Georgia Power under "Retail Regulatory Matters – Georgia Power – Fuel Cost Recovery" and "Retail Regulatory Matters – Fuel Cost Recovery," respectively, in Item 8 of the Form 10-K for additional information. As of June 30, 2015 and December 31, 2014, Georgia Power's under recovered fuel balance totaled $106 million and $199 million , respectively. For June 30, 2015 and December 31, 2014, the balance is included in current assets and current assets and other deferred charges and assets, respectively, on Southern Company's and Georgia Power's Condensed Balance Sheets herein. Georgia Power expects to file its next fuel c ase in September 2015. The ultimate outcome of this matter cannot be determined at this time. Fuel cost recovery revenues are adjusted for differences in actual recoverable fuel costs and amounts billed in current regulated rates. Accordingly, changes in the billing factor will not have a significant effect on Southern Company's or Georgia Power's revenues or net income, but will affect cash flow. Nuclear Construction See Note 3 to the financial statements of Southern Company and Georgia Power under "Retail Regulatory Matters – Georgia Power – Nuclear Construction" and "Retail Regulatory Matters – Nuclear Construction," respectively, in Item 8 of the Form 10-K for additional information regarding Georgia Power's construction of Plant Vogtle Units 3 and 4, Vogtle Construction Monitoring (VCM) reports, and pending litigation. In 2008, Georgia Power, acting for itself and as agent for the Vogtle Owners, entered into an agreement (Vogtle 3 and 4 Agreement) with the Contractor, pursuant to which the Contractor agreed to design, engineer, procure, construct, and test Plant Vogtle Units 3 and 4. Under the terms of the Vogtle 3 and 4 Agreement, the Vogtle Owners agreed to pay a purchase price that is subject to certain price escalations and adjustments, including fixed escalation amounts and index-based adjustments, as well as adjustments for change orders, and performance bonuses for early completion and unit performance. The Vogtle 3 and 4 Agreement also provides for liquidated damages upon the Contractor's failure to fulfill the schedule and performance guarantees. The Contractor's liability to the Vogtle Owners for schedule and performance liquidated damages and warranty claims is subject to a cap. In addition, the Vogtle 3 and 4 Agreement provides for limited cost sharing by the Vogtle Owners for Contractor costs under certain conditions (which have not occurred), with maximum additional capital costs under this provision attributable to Georgia Power (based on Georgia Power's ownership interest) of approximately $114 million . Each Vogtle Owner is severally (and not jointly) liable for its proportionate share, based on its ownership interest, of all amounts owed to the Contractor under the Vogtle 3 and 4 Agreement. Georgia Power's proportionate share is 45.7% . Certain payment obligations of Westinghouse and CB&I Stone & Webster, Inc. (formerly known as Stone & Webster, Inc.) under the Vogtle 3 and 4 Agreement are guaranteed by Toshiba Corporation and The Shaw Group Inc. (a subsidiary of Chicago Bridge & Iron Company, N.V.), respectively. In the event of certain credit rating downgrades of any Vogtle Owner, such Vogtle Owner will be required to provide a letter of credit or other credit enhancement. The Vogtle Owners may terminate the Vogtle 3 and 4 Agreement at any time for their convenience, provided that the Vogtle Owners will be required to pay certain termination costs. The Contractor may terminate the Vogtle 3 and 4 Agreement under certain circumstances, including certain Vogtle Owner suspension or delays of work, action by a governmental authority to permanently stop work, certain breaches of the Vogtle 3 and 4 Agreement by the Vogtle Owners, Vogtle Owner insolvency, and certain other events. In 2009, the NRC issued an Early Site Permit and Limited Work Authorization which allowed limited work to begin on Plant Vogtle Units 3 and 4. The NRC certified the Westinghouse Design Control Document, as amended (DCD), for the AP1000 nuclear reactor design, in late 2011, and issued combined construction and operating licenses (COLs) in early 2012. Receipt of the COLs allowed full construction to begin. There have been technical and procedural challenges to the construction and licensing of Plant Vogtle Units 3 and 4, at the federal and state level, and additional challenges are expected as construction proceeds. In 2012, the Vogtle Owners and the Contractor began negotiations regarding the costs associated with design changes to the DCD and the delays in the timing of approval of the DCD and issuance of the COLs, including the assertion by the Contractor that the Vogtle Owners are responsible for these costs under the terms of the Vogtle 3 and 4 Agreement. Also in 2012, Georgia Power and the other Vogtle Owners filed suit against the Contractor in the U.S. District Court for the Southern District of Georgia seeking a declaratory judgment that the Vogtle Owners are not responsible for these costs. In 2012, the Contractor also filed suit against Georgia Power and the other Vogtle Owners in the U.S. District Court for the District of Columbia alleging the Vogtle Owners are responsible for these costs. In 2013, the U.S. District Court for the District of Columbia dismissed the Contractor's suit, ruling that the proper venue is the U.S. District Court for the Southern District of Georgia. On March 10, 2015, the U.S. Court of Appeals for the District of Columbia Circuit affirmed the District Court's decision. The portion of additional costs claimed by the Contractor in its initial complaint that would be attributable to Georgia Power (based on Georgia Power's ownership interest) is approximately $425 million in 2008 dollars (approximately $591 million in 2015 dollars). The Contractor also asserted it is entitled to extensions of the guaranteed substantial completion dates of April 2016 and April 2017 for Plant Vogtle Units 3 and 4, respectively. In May 2014, the Contractor filed an amended counterclaim to the suit pending in the U.S. District Court for the Southern District of Georgia alleging that (i) the design changes to the DCD imposed by the NRC delayed module production and the impacts to the Contractor are recoverable by the Contractor under the Vogtle 3 and 4 Agreement and (ii) the changes to the basemat rebar design required by the NRC caused additional costs and delays recoverable by the Contractor under the Vogtle 3 and 4 Agreement. The Contractor did not specify in its amended counterclaim the amounts relating to these new allegations; however, the Contractor subsequently asserted estimated minimum damages related to the amended counterclaim (based on Georgia Power's ownership interest) of approximately $113 million in 2014 dollars (approximately $118 million in 2015 dollars). In June 2015, the Contractor updated its estimated damages under the initial complaint and the amended counterclaim to an aggregate (based on Georgia Power's ownership interest) of approximately $714 million (in 2015 dollars). The Contractor may from time to time continue to assert that it is entitled to additional payments with respect to these allegations, any of which could be substantial. Georgia Power has not agreed to the proposed cost or to any changes to the guaranteed substantial completion dates or that the Vogtle Owners have any responsibility for costs related to these issues. Litigation is ongoing and Georgia Power intends to vigorously defend the positions of the Vogtle Owners. Georgia Power also expects negotiations with the Contractor to continue with respect to cost and schedule. During such negotiations the parties may reach a mutually acceptable compromise of their positions. Georgia Power is required to file semi-annual VCM reports with the Georgia PSC by February 28 and August 31 each year. If the projected certified construction capital costs to be borne by Georgia Power increase by 5% or the projected in-service dates are significantly extended, Georgia Power is required to seek an amendment to the Plant Vogtle Units 3 and 4 certificate from the Georgia PSC. Georgia Power's eighth VCM report filed in 2013 requested an amendment to the certificate to increase the estimated in-service capital cost of Plant Vogtle Units 3 and 4 from $4.4 billion to $4.8 billion and to extend the estimated in-service dates to the fourth quarter 2017 and the fourth quarter 2018 for Plant Vogtle Units 3 and 4, respectively. In 2013, the Georgia PSC approved a stipulation (2013 Stipulation) entered into by Georgia Power and the Georgia PSC staff to waive the requirement to amend the Plant Vogtle Units 3 and 4 certificate, until the completion of Plant Vogtle Unit 3, or earlier if deemed appropriate by the Georgia PSC and Georgia Power. The Georgia PSC has approved eleven VCM reports covering the periods through June 30, 2014, including construction capital costs incurred, which through that date totaled $2.8 billion . On January 29, 2015, Georgia Power announced it was notified by the Contractor of the Contractor's revised forecast for completion of Plant Vogtle Units 3 and 4, which would incrementally delay the previously disclosed estimated in-service dates by 18 months (from the fourth quarter of 2017 to the second quarter of 2019 for Unit 3 and from the fourth quarter of 2018 to the second quarter of 2020 for Unit 4). Georgia Power believes that, pursuant to the Vogtle 3 and 4 Agreement, the Contractor is responsible for the Contractor's costs related to the Contractor's delay (including any related construction and mitigation costs, which could be material) and that the Vogtle Owners are entitled to recover liquidated damages for the Contractor's delay beyond the guaranteed substantial completion dates of April 2016 and April 2017 for Plant Vogtle Units 3 and 4, respectively. Consistent with the Contractor's position in the pending litigation described above, Georgia Power expects the Contractor to contest any claims for liquidated damages and to assert that the Vogtle Owners are responsible for additional costs related to the Contractor's delay. On February 27, 2015, Georgia Power filed its twelfth VCM report with the Georgia PSC covering the period from July 1 through December 31, 2014, which requested approval for an additional $0.2 billion of construction capital costs incurred during that period. The twelfth VCM report also reflected the Contractor's revised forecast for completion of Plant Vogtle Units 3 and 4 as well as additional estimated owner-related costs, which include approximately $10 million per month expected to result from the Contractor's proposed 18 -month delay, including property taxes, oversight costs, compliance costs, and other operational readiness costs. No Contractor costs related to the Contractor's proposed 18 -month delay were included in the twelfth VCM report. Additionally, while Georgia Power has not agreed to any change to the guaranteed substantial completion dates, the twelfth VCM report included a requested amendment (Requested Amendment) to the Plant Vogtle Units 3 and 4 certificate to reflect the Contractor's revised forecast, to include the estimated owner's costs associated with the proposed 18 -month Contractor delay, and to increase the estimated total in-service capital cost of Plant Vogtle Units 3 and 4 to $5.0 billion . Georgia Power will continue to incur financing costs of approximately $30 million per month until Plant Vogtle Units 3 and 4 are placed in service. The twelfth VCM report estimated financing costs during the construction period to total approximately $2.5 billion . On April 15, 2015, the Georgia PSC issued a procedural order in connection with the twelfth VCM report. Pursuant to this order, the Georgia PSC deemed the Requested Amendment unnecessary and withdrawn until the completion of construction of Plant Vogtle Unit 3 consistent with the 2013 Stipulation. The Georgia PSC recognized that the certified cost and the 2013 Stipulation do not constitute a cost recovery cap. In accordance with the Georgia Integrated Resource Planning Act, any costs incurred by Georgia Power in excess of the certified amount will be included in rate base, provided Georgia Power shows the costs to be reasonable and prudent. Financing costs up to the certified amount will be collected through the NCCR tariff until the units are placed in service, while financing costs on any construction-related costs in excess of the $4.4 billion certified amount are expected to be recovered through AFUDC. Processes are in place that are designed to assure compliance with the requirements specified in the DCD and the COLs, including inspections by Southern Nuclear and the NRC that occur throughout construction. As a result of such compliance processes, certain license amendment requests have been filed and approved or are pending before the NRC. Various design and other licensing-based compliance issues are expected to arise as construction proceeds, which may result in additional license amendments or require other resolution. If any license amendment requests or other licensing-based compliance issues are not resolved in a timely manner, there may be delays in the project schedule that could result in increased costs either to the Vogtle Owners or the Contractor or to both. As construction continues, the risk remains that ongoing challenges with Contractor performance including additional challenges in its fabrication, assembly,

Fair Value Measurements

Fair Value Measurements	6 Months Ended
	Jun. 30, 2015
Fair Value Disclosures [Abstract]
FAIR VALUE MEASUREMENTS	FAIR VALUE MEASUREMENTS As of June 30, 2015 , assets and liabilities measured at fair value on a recurring basis during the period, together with the associated level of the fair value hierarchy, were as follows: Fair Value Measurements Using As of June 30, 2015: Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Total (in millions) Southern Company Assets: Energy-related derivatives $ — $ 5 $ — $ 5 Interest rate derivatives — 11 — 11 Nuclear decommissioning trusts (a) 677 887 7 1,571 Cash equivalents 533 — — 533 Other investments 9 — 1 10 Total $ 1,219 $ 903 $ 8 $ 2,130 Liabilities: Energy-related derivatives $ — $ 180 $ — $ 180 Interest rate derivatives — 14 — 14 Total $ — $ 194 $ — $ 194 Alabama Power Assets: Energy-related derivatives $ — $ 2 $ — $ 2 Nuclear decommissioning trusts (b) Domestic equity 381 78 — 459 Foreign equity 51 50 — 101 U.S. Treasury and government agency securities — 36 — 36 Corporate bonds 10 121 — 131 Mortgage and asset backed securities — 17 — 17 Other — 6 7 13 Cash equivalents 81 — — 81 Total $ 523 $ 310 $ 7 $ 840 Liabilities: Energy-related derivatives $ — $ 48 $ — $ 48 Interest rate derivatives — 7 — 7 Total $ — $ 55 $ — $ 55 Fair Value Measurements Using As of June 30, 2015: Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Total (in millions) Georgia Power Assets: Energy-related derivatives $ — $ 3 $ — $ 3 Interest rate derivatives — 5 — 5 Nuclear decommissioning trusts (b) (c) Domestic equity 182 1 — 183 Foreign equity — 125 — 125 U.S. Treasury and government agency securities — 95 — 95 Municipal bonds — 78 — 78 Corporate bonds — 169 — 169 Mortgage and asset backed securities — 108 — 108 Other 53 3 — 56 Total $ 235 $ 587 $ — $ 822 Liabilities: Energy-related derivatives $ — $ 17 $ — $ 17 Interest rate derivatives — 4 — 4 Total $ — $ 21 $ — $ 21 Gulf Power Assets: Cash equivalents $ 18 $ — $ — $ 18 Liabilities: Energy-related derivatives — 74 — 74 Mississippi Power Assets: Cash equivalents $ 182 $ — $ — $ 182 Liabilities: Energy-related derivatives — 41 — 41 Southern Power Assets: Cash equivalents $ 206 $ — $ — $ 206 (a) For additional detail, see the nuclear decommissioning trusts sections for Alabama Power and Georgia Power in this table. (b) Excludes receivables related to investment income, pending investment sales, payables related to pending investment purchases, and currencies. (c) Includes the investment securities pledged to creditors and collateral received and excludes payables related to the securities lending program. As of June 30, 2015 , approximately $39 million of the fair market value of Georgia Power's nuclear decommissioning trust funds' securities were on loan to creditors under the funds' managers' securities lending program. Valuation Methodologies The energy-related derivatives primarily consist of over-the-counter financial products for natural gas and physical power products, including, from time to time, basis swaps. These are standard products used within the energy industry and are valued using the market approach. The inputs used are mainly from observable market sources, such as forward natural gas prices, power prices, implied volatility, and overnight index swap interest rates. Interest rate derivatives are also standard over-the-counter financial products valued using the market approach. Inputs for interest rate derivatives include LIBOR interest rates, interest rate futures contracts, and occasionally, implied volatility of interest rate options. See Note (H) herein for additional information on how these derivatives are used. For fair value measurements of the investments within the nuclear decommissioning trusts, external pricing vendors are designated for each asset class with each security specifically assigned a primary pricing source. For investments held within commingled funds, fair value is determined at the end of each business day through the net asset value, which is established by obtaining the underlying securities' individual prices from the primary pricing source. A market price secured from the primary source vendor is then evaluated by management in its valuation of the assets within the trusts. As a general approach, fixed income market pricing vendors gather market data (including indices and market research reports) and integrate relative credit information, observed market movements, and sector news into proprietary pricing models, pricing systems, and mathematical tools. Dealer quotes and other market information, including live trading levels and pricing analysts' judgment, are also obtained when available. Investments in private equity and real estate within Alabama Power's nuclear decommissioning trusts are generally classified as Level 3, as the underlying assets typically do not have observable inputs. The fund manager values these assets using various inputs and techniques depending on the nature of the underlying investments. The fair value of partnerships is determined by aggregating the value of the underlying assets. "Other investments" include investments that are not traded in the open market. The fair value of these investments have been determined based on market factors including comparable multiples and the expectations regarding cash flows and business plan executions. As of June 30, 2015 , the fair value measurements of investments calculated at net asset value per share (or its equivalent), as well as the nature and risks of those investments, were as follows: As of June 30, 2015: Fair Value Unfunded Commitments Redemption Frequency Redemption Notice Period (in millions) Southern Company Nuclear decommissioning trusts: Foreign equity funds $ 125 None Monthly 5 days Equity - commingled funds 50 None Daily Daily Debt - commingled funds 16 None Daily 5 days Other - commingled funds 3 None Daily Not applicable Other - money market funds 53 None Daily Not applicable Trust-owned life insurance 117 None Daily 15 days Cash equivalents: Money market funds 533 None Daily Not applicable Alabama Power Nuclear decommissioning trusts: Equity - commingled funds $ 50 None Daily Daily Debt - commingled funds 16 None Daily 5 days Trust-owned life insurance 117 None Daily 15 days Cash equivalents: Money market funds 81 None Daily Not applicable Georgia Power Nuclear decommissioning trusts: Foreign equity funds $ 125 None Monthly 5 days Other - commingled funds 3 None Daily Not applicable Other - money market funds 53 None Daily Not applicable Gulf Power Cash equivalents: Money market funds $ 18 None Daily Not applicable Mississippi Power Cash equivalents: Money market funds $ 182 None Daily Not applicable Southern Power Cash equivalents: Money market funds $ 206 None Daily Not applicable The NRC requires licensees of commissioned nuclear power reactors to establish a plan for providing reasonable assurance of funds for future decommissioning. Alabama Power and Georgia Power have external trust funds (the Funds) to comply with the NRC's regulations. The foreign equity fund in Georgia Power's nuclear decommissioning trusts seeks to provide long-term capital appreciation. In pursuing this investment objective, the foreign equity fund primarily invests in a diversified portfolio of equity securities of foreign companies, including those in emerging markets. These equity securities may include, but are not limited to, common stocks, preferred stocks, real estate investment trusts, convertible securities, depositary receipts (including American depositary receipts, European depositary receipts, and global depositary receipts), and rights and warrants to buy common stocks. Georgia Power may withdraw all or a portion of its investment on the last business day of each month subject to a minimum withdrawal of $1 million , provided that a minimum investment of $10 million remains. If notices of withdrawal exceed 20% of the aggregate value of the foreign equity fund, then the foreign equity fund's board may refuse to permit the withdrawal of all such investments and may scale down the amounts to be withdrawn pro rata and may further determine that any withdrawal that has been postponed will have priority on the subsequent withdrawal date. The other-commingled funds and other-money market funds in Georgia Power's nuclear decommissioning trusts are invested primarily in a diversified portfolio of high-quality, short-term, liquid debt securities. The funds represent cash collateral received under the Funds' managers' securities lending program and/or excess cash held within each separate investment account. The primary objective of the funds is to provide a high level of current income consistent with stability of principal and liquidity. The funds invest primarily in, but not limited to, commercial paper, floating and variable rate demand notes, debt securities issued or guaranteed by the U.S. government or its agencies or instrumentalities, time deposits, repurchase agreements, municipal obligations, notes, and other high-quality short-term liquid debt securities that mature in 90 days or less. Redemptions are available on a same day basis up to the full amount of the investment in the fund. See Note 1 to the financial statements of Southern Company and Georgia Power under "Nuclear Decommissioning" in Item 8 of the Form 10-K for additional information. Alabama Power's nuclear decommissioning trusts include investments in Trust-Owned Life Insurance (TOLI). The taxable nuclear decommissioning trusts invest in the TOLI in order to minimize the impact of taxes on the portfolios and can draw on the value of the TOLI through death proceeds, loans against the cash surrender value, and/or the cash surrender value, subject to legal restrictions. The amounts reported in the table above reflect the fair value of investments the insurer has made in relation to the TOLI agreements. The nuclear decommissioning trusts do not own the underlying investments, but the fair value of the investments approximates the cash surrender value of the TOLI policies. The investments made by the insurer are in commingled funds. These commingled funds, along with other equity and debt commingled funds held in Alabama Power's nuclear decommissioning trusts, primarily include investments in domestic and international equity securities and predominantly high-quality fixed income securities. These fixed income securities may include U.S. Treasury and government agency fixed income securities, non-U.S. government and agency fixed income securities, domestic and foreign corporate fixed income securities, and mortgage and asset backed securities. The passively managed funds seek to replicate the performance of a related index. The actively managed funds seek to exceed the performance of a related index through security analysis and selection. See Note 1 to the financial statements of Southern Company and Alabama Power under "Nuclear Decommissioning" in Item 8 of the Form 10-K for additional information. Southern Company, Alabama Power, and Georgia Power continue to elect the option to fair value investment securities held in the nuclear decommissioning trust funds. For the three and six months ended June 30, 2015 , the change in fair value of the funds, including reinvested interest and dividends reduced by the funds' expenses, increased by $44 million and $109 million , respectively, at Southern Company. For the three and six months ended June 30, 2015 , Alabama Power recorded an increase in fair value of $50 million and $97 million , respectively, as an increase in regulatory liabilities. For the three and six months ended June 30, 2015 , Georgia Power recorded a decrease in fair value of $6 million and an increase of $12 million , respectively, as a reduction of its regulatory asset related to its ARO. The money market funds are short-term investments of excess funds in various money market mutual funds, which are portfolios of short-term debt securities. The money market funds are regulated by the SEC and typically receive the highest rating from credit rating agencies. Regulatory and rating agency requirements for money market funds include minimum credit ratings and maximum maturities for individual securities and a maximum weighted average portfolio maturity. Redemptions are available on a same day basis up to the full amount of the investment in the money market funds. As of June 30, 2015 , other financial instruments for which the carrying amount did not equal fair value were as follows: Carrying Amount Fair Value (in millions) Long-term debt, including securities due within one year: Southern Company $ 26,156 $ 26,973 Alabama Power $ 7,295 $ 7,621 Georgia Power $ 10,379 $ 10,767 Gulf Power $ 1,370 $ 1,438 Mississippi Power $ 2,275 $ 2,246 Southern Power $ 2,262 $ 2,302 The fair values are determined using Level 2 measurements and are based on quoted market prices for the same or similar issues or on the current rates available to the registrants.

Stockholders' Equity

Stockholders' Equity	6 Months Ended
	Jun. 30, 2015
Equity [Abstract]
STOCKHOLDERS' EQUITY	STOCKHOLDERS' EQUITY Earnings per Share For Southern Company, the only difference in computing basic and diluted earnings per share is attributable to awards outstanding under the stock option and performance share plans. See Note 8 to the financial statements of Southern Company in Item 8 of the Form 10-K for information on the stock option and performance share plans. The effect of both stock options and performance share award units was determined using the treasury stock method. Shares used to compute diluted earnings per share were as follows: Three Months Ended June 30, 2015 Three Months Ended June 30, 2014 Six Months Ended June 30, 2015 Six Months Ended June 30, 2014 (in millions) As reported shares 909 895 910 892 Effect of options and performance share award units 3 4 4 4 Diluted shares 912 899 914 896 Stock options and performance share award units that were not included in the diluted earnings per share calculation because they were anti-dilutive were 15 million and 1 million for the three and six months ended June 30, 2015 , respectively, and were 8 million and 17 million for the three and six months ended June 30, 2014 , respectively. Changes in Stockholders' Equity The following table presents year-to-date changes in stockholders' equity of Southern Company: Number of Common Shares Common Preferred and Preference Stock of Subsidiaries Total Issued Treasury Noncontrolling Interest (*) (in thousands) (in millions) Balance at December 31, 2014 908,502 (725 ) $ 19,949 $ 756 $ 221 $ 20,926 Net income after dividends on preferred and preference stock — — 1,138 — — 1,138 Other comprehensive income (loss) — — 7 — — 7 Stock issued 3,222 — 117 — — 117 Stock-based compensation — — 66 — — 66 Stock repurchased, at cost — (2,599 ) (115 ) — — (115 ) Cash dividends on common stock — — (972 ) — — (972 ) Preference stock redemption — — — (150 ) — (150 ) Contributions from noncontrolling interest — — — — 135 135 Distributions to noncontrolling interest — — — — (5 ) (5 ) Net income attributable to noncontrolling interest — — — — 4 4 Other — 25 (8 ) 3 — (5 ) Balance at June 30, 2015 911,724 (3,299 ) $ 20,182 $ 609 $ 355 $ 21,146 Balance at December 31, 2013 892,733 (5,647 ) $ 19,008 $ 756 $ — $ 19,764 Net income after dividends on preferred and preference stock — — 962 — — 962 Other comprehensive income (loss) — — 4 — — 4 Treasury stock re-issued — 4,739 216 — — 216 Stock issued 3,898 — 161 — — 161 Stock repurchased, at cost — — (5 ) — — (5 ) Cash dividends on common stock — — (920 ) — — (920 ) Other — (27 ) — — — — Balance at June 30, 2014 896,631 (935 ) $ 19,426 $ 756 $ — $ 20,182 (*) Primarily related to Southern Power Company. Stock Repurchased On March 2, 2015, Southern Company announced a program to repurchase up to 20 million shares of Southern Company common stock to offset all or a portion of the incremental shares issued under its employee and director equity compensation plans, including through stock option exercises, until December 31, 2017. Under this program, approximately 2.6 million shares have been repurchased through June 30, 2015 at a total cost of approximately $115 million . Pursuant to board approval, Southern Company may repurchase shares through open market purchases or privately negotiated transactions, including accelerated or other share repurchase programs, in accordance with applicable securities laws.

Financing

Financing	6 Months Ended
	Jun. 30, 2015
Debt Disclosure [Abstract]
FINANCING	FINANCING Bank Credit Arrangements Bank credit arrangements provide liquidity support to the registrants' commercial paper borrowings and the traditional operating companies' variable rate pollution control revenue bonds. The amount of variable rate pollution control revenue bonds outstanding requiring liquidity support as of June 30, 2015 was approximately $1.9 billion (comprised of approximately $810 million at Alabama Power, $970 million at Georgia Power, $69 million at Gulf Power, and $40 million at Mississippi Power). In addition, at June 30, 2015 , the traditional operating companies had approximately $368 million (comprised of approximately $200 million at Alabama Power, $122 million at Georgia Power, and $46 million at Gulf Power) of fixed rate pollution control revenue bonds outstanding that were required to be reoffered within the next 12 months. See Note 6 to the financial statements of each registrant under "Bank Credit Arrangements" in Item 8 of the Form 10-K for additional information. See "Financing Activities" herein for additional information. The following table outlines the committed credit arrangements by company as of June 30, 2015 : Expires Executable Term Loans Due Within One Year Company 2015 2016 2017 2018 Total Unused One Year Two Years Term Out No Term Out (in millions) (in millions) (in millions) (in millions) Southern Company $ — $ — $ — $ 1,000 $ 1,000 $ 1,000 $ — $ — $ — $ — Alabama Power 154 124 — 1,030 1,308 1,307 58 — 58 170 Georgia Power — 150 — 1,600 1,750 1,737 — — — 150 Gulf Power 20 225 30 — 275 275 50 — 50 195 Mississippi Power 40 255 — — 295 265 30 40 70 225 Southern Power — — — 500 500 466 — — — — Other 25 45 — — 70 70 20 — 20 50 Total $ 239 $ 799 $ 30 $ 4,130 $ 5,198 $ 5,120 $ 158 $ 40 $ 198 $ 790 Subject to applicable market conditions, Southern Company and its subsidiaries expect to renew or replace their bank credit arrangements as needed, prior to expiration. In connection therewith, Southern Company and its subsidiaries may extend the maturity dates and/or increase or decrease the lending commitments thereunder. Financing Activities The following table outlines the long-term debt financing activities for Southern Company and its subsidiaries for the first six months of 2015 : Company (a) Senior Note Issuances Senior Note Redemptions Revenue Bond Issuances and Reofferings of Purchased Bonds (b) Revenue Other Long-Term Debt Issuances Other Long-Term Debt Redemptions and Maturities (c) (in millions) Southern Company $ 600 $ — $ — $ — $ — $ — Alabama Power 975 250 80 134 — — Georgia Power — 125 170 65 600 5 Mississippi Power — — — — — 351 Southern Power 650 — — — — — Other — — — — — 9 Total $ 2,225 $ 375 $ 250 $ 199 $ 600 $ 365 (a) Gulf Power did not issue or redeem any long-term debt during the first six months of 2015 . (b) Includes reoffering by Alabama Power of $80 million aggregate principal amount of revenue bonds previously purchased and held by Alabama Power since April 2015 and reofferings by Georgia Power of $104.6 million and $65 million aggregate principal amount of revenue bonds previously purchased and held by Georgia Power since 2013 and April 2015, respectively. (c) Includes reductions in capital lease obligations resulting from cash payments under capital leases. Southern Company In June 2015, Southern Company issued $600 million aggregate principal amount of Series 2015A 2.750% Senior Notes due June 15, 2020. The proceeds were used to pay a portion of Southern Company's outstanding short-term indebtedness and for other general corporate purposes. Alabama Power In March 2015, Alabama Power issued $550 million aggregate principal amount of Series 2015A 3.750% Senior Notes due March 1, 2045. The proceeds were used to redeem $250 million aggregate principal amount of Series DD 5.65% Senior Notes due March 15, 2035 and for general corporate purposes, including Alabama Power's continuous construction program . In April 2015, Alabama Power purchased and held $80 million aggregate principal amount of Industrial Development Board of the City of Mobile, Alabama Pollution Control Revenue Bonds (Alabama Power Company Barry Plant Project), Series 2007-B. Alabama Power reoffered these bonds to the public in May 2015. Also in April 2015, Alabama Power issued $175 million additional aggregate principal amount of its Series 2015A 3.750% Senior Notes due March 1, 2045 (Additional Series 2015A Senior Notes) and $250 million aggregate principal amount of its Series 2015B 2.800% Senior Notes due April 1, 2025 (Series 2015B Senior Notes). A portion of the proceeds of the Additional Series 2015A Senior Notes and the Series 2015B Senior Notes were used to redeem in May 2015 6.48 million shares ( $162 million aggregate stated capital) of Alabama Power's 5.20% Class A Preferred Stock at a redemption price of $25 per share plus accrued and unpaid dividends to the redemption date, 4.0 million shares ( $100 million aggregate stated capital) of Alabama Power's 5.30% Class A Preferred Stock at a redemption price of $25 per share plus accrued and unpaid dividends to the redemption date, and 6.0 million shares ( $150 million aggregate stated capital) of Alabama Power's 5.625% Series Preference Stock at a redemption price of $25 per share plus accrued and unpaid dividends to the redemption date, and the remaining net proceeds were used for general corporate purposes, including Alabama Power's continuous construction program. Georgia Power In April 2015, Georgia Power purchased and held $65 million aggregate principal amount of Development Authority of Burke County (Georgia) Pollution Control Revenue Bonds (Georgia Power Company Plant Vogtle Project), Second Series 2008. Georgia Power reoffered these bonds to the public in May 2015. In May 2015, Georgia Power reoffered to the public $104.6 million aggregate principal amount of Development Authority of Burke County (Georgia) Pollution Control Revenue Bonds (Georgia Power Company Plant Vogtle Project), First Series 2013, which had been previously purchased and held by Georgia Power since 2013. In June 2015, Georgia Power made additional borrowings under the FFB Credit Facility in an aggregate principal amount of $600 million . The interest rate applicable to the $600 million principal amount is 3.283% for an interest period that extends to the final maturity date of February 20, 2044. The proceeds were used to reimburse Georgia Power for Eligible Project Costs relating to the construction of Plant Vogtle Units 3 and 4. Georgia Power settled $350 million of interest rate swaps related to this borrowing for approximately $6 million , which will be amortized to interest expense over 10 years . Mississippi Power In April 2015, Mississippi Power entered into two floating rate bank loans with a maturity date of April 1, 2016, in an aggregate principal amount of $475 million , bearing interest based on one-month LIBOR . The proceeds of these loans were used for the repayment of term loans in an aggregate principal amount of $275 million , working capital, and other general corporate purposes, including Mississippi Power's ongoing construction program. Mississippi Power also amended three outstanding floating rate bank loans for an aggregate principal amount of $425 million which, among other things, extended the maturity dates from various dates in 2015 to April 1, 2016. In June 2015, Mississippi Power issued an 18 -month floating rate promissory note to Southern Company bearing interest based on one-month LIBOR . This note was for an aggregate principal amount of approximately $301 million , the amount paid by Southern Company to SMEPA pursuant to Southern Company's guarantee of the return of SMEPA's deposit in connection with the termination of the APA. See Note (B) under "Integrated Coal Gasification Combined Cycle – Termination of Proposed Sale of Undivided Interest to SMEPA" herein for additional information. Southern Power In May 2015, Southern Power Company issued $350 million aggregate principal amount of Series 2015A 1.500% Senior Notes due June 1, 2018 and $300 million aggregate principal amount of Series 2015B 2.375% Senior Notes due June 1, 2020. The proceeds were used to repay a portion of its outstanding short-term indebtedness, for other general corporate purposes, including Southern Power's growth strategy and continuous construction program, and for a portion of the subsequent repayment at maturity of $525 million aggregate principal amount of Southern Power Company's 4.875% Senior Notes on July 15, 2015.

Retirement Benefits

Retirement Benefits	6 Months Ended
	Jun. 30, 2015
Compensation and Retirement Disclosure [Abstract]
RETIREMENT BENEFITS	RETIREMENT BENEFITS Southern Company has a defined benefit, trusteed, pension plan covering substantially all employees. The qualified pension plan is funded in accordance with requirements of the Employee Retirement Income Security Act of 1974, as amended. No mandatory contributions to the qualified pension plan are anticipated for the year ending December 31, 2015. Southern Company also provides certain defined benefit pension plans for a selected group of management and highly compensated employees. Benefits under these non-qualified pension plans are funded on a cash basis. In addition, Southern Company provides certain medical care and life insurance benefits for retired employees through other postretirement benefit plans. The traditional operating companies fund related other postretirement trusts to the extent required by their respective regulatory commissions. See Note 2 to the financial statements of Southern Company, Alabama Power, Georgia Power, Gulf Power, and Mississippi Power in Item 8 of the Form 10-K for additional information. Components of the net periodic benefit costs for the three and six months ended June 30, 2015 and 2014 were as follows: Pension Plans Southern Company Alabama Power Georgia Power Gulf Power Mississippi Power (in millions) Three Months Ended June 30, 2015 Service cost $ 64 $ 15 $ 18 $ 3 $ 3 Interest cost 111 27 39 5 6 Expected return on plan assets (181 ) (44 ) (63 ) (8 ) (9 ) Amortization: Prior service costs 7 1 2 — 1 Net (gain)/loss 54 13 19 2 2 Net cost $ 55 $ 12 $ 15 $ 2 $ 3 Six Months Ended June 30, 2015 Service cost $ 128 $ 30 $ 36 $ 6 $ 6 Interest cost 222 53 77 10 11 Expected return on plan assets (362 ) (89 ) (126 ) (16 ) (17 ) Amortization: Prior service costs 13 3 5 — 1 Net (gain)/loss 108 27 38 5 5 Net cost $ 109 $ 24 $ 30 $ 5 $ 6 Three Months Ended June 30, 2014 Service cost $ 54 $ 12 $ 15 $ 1 $ 2 Interest cost 108 26 38 5 5 Expected return on plan assets (162 ) (42 ) (56 ) (7 ) (7 ) Amortization: Prior service costs 7 2 2 1 1 Net (gain)/loss 27 8 10 1 1 Net cost $ 34 $ 6 $ 9 $ 1 $ 2 Six Months Ended June 30, 2014 Service cost $ 107 $ 24 $ 31 $ 4 $ 5 Interest cost 217 52 76 10 10 Expected return on plan assets (323 ) (84 ) (113 ) (14 ) (14 ) Amortization: Prior service costs 13 3 5 1 1 Net (gain)/loss 55 16 20 2 2 Net cost $ 69 $ 11 $ 19 $ 3 $ 4 Postretirement Benefits Southern Company Alabama Power Georgia Power Gulf Power Mississippi Power (in millions) Three Months Ended June 30, 2015 Service cost $ 5 $ 2 $ 1 $ — $ 1 Interest cost 20 5 9 1 1 Expected return on plan assets (14 ) (7 ) (6 ) (1 ) (1 ) Amortization: Prior service costs 1 — — — — Net (gain)/loss 4 1 3 — — Net cost $ 16 $ 1 $ 7 $ — $ 1 Six Months Ended June 30, 2015 Service cost $ 11 $ 3 $ 3 $ — $ 1 Interest cost 39 10 17 2 2 Expected return on plan assets (29 ) (13 ) (12 ) (1 ) (1 ) Amortization: Prior service costs 2 1 — — — Net (gain)/loss 9 1 6 — — Net cost $ 32 $ 2 $ 14 $ 1 $ 2 Three Months Ended June 30, 2014 Service cost $ 6 $ 2 $ 1 $ 1 $ 1 Interest cost 20 5 9 1 1 Expected return on plan assets (15 ) (7 ) (7 ) (1 ) (1 ) Amortization: Prior service costs 1 1 — — — Net (gain)/loss — — 1 — — Net cost $ 12 $ 1 $ 4 $ 1 $ 1 Six Months Ended June 30, 2014 Service cost $ 11 $ 3 $ 3 $ 1 $ 1 Interest cost 40 10 17 2 2 Expected return on plan assets (30 ) (13 ) (13 ) (1 ) (1 ) Amortization: Prior service costs 2 2 — — — Net (gain)/loss 1 — 1 — — Net cost $ 24 $ 2 $ 8 $ 2 $ 2

Income Taxes

Income Taxes	6 Months Ended
	Jun. 30, 2015
Income Tax Disclosure [Abstract]
INCOME TAXES	INCOME TAXES Current and Deferred Income Taxes State of Georgia Tax Benefits During the second quarter 2015, an agreement was reached with the Georgia Department of Revenue that will allow Southern Company to utilize a net operating loss carryforward over a four-year period beginning in 2017. Consequently, Southern Company reversed the related valuation allowance and recognized approximately $24 million in net tax benefits as of June 30, 2015. See Note 5 to the financial statements of Southern Company under "Current and Deferred Income Taxes" in Item 8 of the Form 10-K for additional information. Southern Power ITC Carryforwards Southern Power had federal ITC carryforwards which are expected to result in $428 million of federal income tax benefits as of June 30, 2015, compared to $305 million as of December 31, 2014. The carryforwards as of June 30, 2015 expire between 2031 and 2035 and are expected to be utilized by the end of 2016. Effective Tax Rate See Note 5 to the financial statements of each registrant in Item 8 of the Form 10-K for additional tax information. Mississippi Power Mississippi Power's effective tax rate was 19.0% for the six months ended June 30, 2015 compared to (51.1)% for the corresponding period in 2014 . The increase was primarily due to higher net income, partially offset by a decrease in non-taxable AFUDC equity related to the construction of the Kemper IGCC. Southern Power Southern Power's effective tax rate was 13.7% for the six months ended June 30, 2015 compared to 0.3% for the corresponding period in 2014 . The increase was primarily due to beneficial changes that impacted 2014 state income taxes, which were partially offset by increased federal income tax benefits related to ITCs in the current year. Unrecognized Tax Benefits See Note 5 to the financial statements of Southern Company under "Unrecognized Tax Benefits" in Item 8 of the Form 10-K for additional information. Changes during 2015 for unrecognized tax benefits were as follows: Mississippi Power Southern Power Southern Company (in millions) Unrecognized tax benefits as of December 31, 2014 $ 165 $ 5 $ 170 Tax positions from current periods — 2 2 Tax positions from prior periods 230 — 231 Reductions due to settlements (5 ) — (5 ) Balance as of June 30, 2015 $ 390 $ 7 $ 398 The tax positions from prior periods relate primarily to 2008 through 2013 amended federal income tax returns that were filed to include deductions for Kemper IGCC-related R&E expenditures. See "Section 174 Research and Experimental Deduction" herein for additional information. The impact on the effective tax rate, if recognized, was as follows: As of June 30, 2015 As of December 31, 2014 Mississippi Power Southern Power Southern Company Southern Company (in millions) Tax positions impacting the effective tax rate $ — $ 7 $ 8 $ 10 Tax positions not impacting the effective tax rate 390 — 390 160 Balance of unrecognized tax benefits $ 390 $ 7 $ 398 $ 170 The tax positions impacting the effective tax rate primarily relate to federal income tax benefits related to ITCs. The tax positions not impacting the effective tax rate relate to deductions for Kemper IGCC-related R&E expenditures. See "Section 174 Research and Experimental Deduction" herein for additional information. These amounts are presented on a gross basis without considering the related federal or state income tax impact. Section 174 Research and Experimental Deduction Southern Company reduced tax payments for 2014, and included in its 2013 consolidated federal income tax return deductions for R&E expenditures related to the Kemper IGCC. In May 2015, Southern Company amended its 2008 through 2013 federal income tax returns to include deductions for Kemper IGCC-related R&E expenditures. The Kemper IGCC is based on first-of-a-kind technology, and Mississippi Power and Southern Company believe that a significant portion of the plant costs qualify as deductible R&E expenditures under Internal Revenue Code Section 174. The IRS is currently reviewing the underlying support for the deduction, but has not completed its audit of these expenditures. Due to the uncertainty related to this tax position, Mississippi Power and Southern Company had related unrecognized tax benefits associated with these R&E deductions of approximately $390 million and associated interest of $5 million as of June 30, 2015 . The ultimate outcome of this matter cannot be determined at this time.

Derivatives

Derivatives	6 Months Ended
	Jun. 30, 2015
Derivative Instruments and Hedging Activities Disclosure [Abstract]
DERIVATIVES	DERIVATIVES Southern Company, the traditional operating companies, and Southern Power are exposed to market risks, primarily commodity price risk and interest rate risk. To manage the volatility attributable to these exposures, each company nets its exposures, where possible, to take advantage of natural offsets and enters into various derivative transactions for the remaining exposures pursuant to each company's policies in areas such as counterparty exposure and risk management practices. Each company's policy is that derivatives are to be used primarily for hedging purposes and mandates strict adherence to all applicable risk management policies. Derivative positions are monitored using techniques including, but not limited to, market valuation, value at risk, stress testing, and sensitivity analysis. Derivative instruments are recognized at fair value in the balance sheets as either assets or liabilities and are presented on a gross basis. See Note (C) herein for additional information. In the statements of cash flows, the cash impacts of settled energy-related and interest rate derivatives are recorded as operating activities. Energy-Related Derivatives The traditional operating companies and Southern Power enter into energy-related derivatives to hedge exposures to electricity, gas, and other fuel price changes. However, due to cost-based rate regulations and other various cost recovery mechanisms, the traditional operating companies have limited exposure to market volatility in commodity fuel prices and prices of electricity. Each of the traditional operating companies manages fuel-hedging programs, implemented per the guidelines of their respective state PSCs, through the use of financial derivative contracts, which is expected to continue to mitigate price volatility. The traditional operating companies (with respect to wholesale generating capacity) and Southern Power have limited exposure to market volatility in commodity fuel prices and prices of electricity because their long-term sales contracts shift substantially all fuel cost responsibility to the purchaser. However, the traditional operating companies and Southern Power may be exposed to market volatility in energy-related commodity prices to the extent any uncontracted wholesale generating capacity is used to sell electricity. To mitigate residual risks relative to movements in electricity prices, the traditional operating companies and Southern Power may enter into physical fixed-price contracts for the purchase and sale of electricity through the wholesale electricity market. To mitigate residual risks relative to movements in gas prices, the traditional operating companies and Southern Power may enter into fixed-price contracts for natural gas purchases; however, a significant portion of contracts are priced at market. Energy-related derivative contracts are accounted for under one of three methods: • Regulatory Hedges — Energy-related derivative contracts which are designated as regulatory hedges relate primarily to the traditional operating companies' fuel-hedging programs, where gains and losses are initially recorded as regulatory liabilities and assets, respectively, and then are included in fuel expense as the underlying fuel is used in operations and ultimately recovered through the respective fuel cost recovery clauses. • Cash Flow Hedges — Gains and losses on energy-related derivatives designated as cash flow hedges which are mainly used to hedge anticipated purchases and sales and are initially deferred in OCI before being recognized in the statements of income in the same period as the hedged transactions are reflected in earnings. • Not Designated — Gains and losses on energy-related derivative contracts that are not designated or fail to qualify as hedges are recognized in the statements of income as incurred. Some energy-related derivative contracts require physical delivery as opposed to financial settlement, and this type of derivative is both common and prevalent within the electric industry. When an energy-related derivative contract is settled physically, any cumulative unrealized gain or loss is reversed and the contract price is recognized in the respective line item representing the actual price of the underlying goods being delivered. At June 30, 2015 , the net volume of energy-related derivative contracts for natural gas positions for the Southern Company system, together with the longest hedge date over which the respective entity is hedging its exposure to the variability in future cash flows for forecasted transactions and the longest non-hedge date for derivatives not designated as hedges, were as follows: Net Purchased mmBtu Longest Hedge Date Longest Non-Hedge Date (in millions) Southern Company 220 2020 2017 Alabama Power 49 2018 — Georgia Power 47 2017 — Gulf Power 80 2020 — Mississippi Power 43 2018 — Southern Power 1 2015 2017 In addition to the volumes discussed in the above table, the traditional operating companies and Southern Power enter into physical natural gas supply contracts that provide the option to sell back excess gas due to operational constraints. The maximum expected volume of natural gas subject to such a feature is 5 million mmBtu for Southern Company, 1 million mmBtu for Alabama Power, 3 million mmBtu for Georgia Power, and 1 million mmBtu for Southern Power. For cash flow hedges, the amounts expected to be reclassified from accumulated OCI to earnings for the next 12-month period ending June 30, 2016 are immaterial for all registrants. Interest Rate Derivatives Southern Company and certain subsidiaries may also enter into interest rate derivatives to hedge exposure to changes in interest rates. The derivatives employed as hedging instruments are structured to minimize ineffectiveness. Derivatives related to existing variable rate securities or forecasted transactions are accounted for as cash flow hedges where the effective portion of the derivatives' fair value gains or losses is recorded in OCI and is reclassified into earnings at the same time the hedged transactions affect earnings, with any ineffectiveness recorded directly to earnings. Derivatives related to existing fixed rate securities are accounted for as fair value hedges, where the derivatives' fair value gains or losses and hedged items' fair value gains or losses are both recorded directly to earnings, providing an offset, with any difference representing ineffectiveness. At June 30, 2015 , the following interest rate derivatives were outstanding: Notional Amount Interest Rate Received Weighted Average Interest Rate Paid Hedge Maturity Date Fair Value 2015 (in millions) (in millions) Cash Flow Hedges of Forecasted Debt Alabama Power $ 200 3-month 2.93% October 2025 $ (7 ) Georgia Power 350 3-month 2.57% November 2025 (1 ) Cash Flow Hedges of Existing Debt Georgia Power 250 3-month 0.75% March 2016 — Georgia Power 200 3-month 1.01% August 2016 — Fair Value Hedges on Existing Debt Southern Company 250 1.30% 3-month August 2017 2 Southern Company 300 2.75% 3-month LIBOR + 0.92% June 2020 1 Georgia Power 250 5.40% 3-month June 2018 1 Georgia Power 200 4.25% 3-month December 2019 1 Total $ 2,000 $ (3 ) The estimated pre-tax gains (losses) that will be reclassified from accumulated OCI to interest expense for the next 12-month period ending June 30, 2016 are immaterial for all registrants. Southern Company and certain subsidiaries have deferred gains and losses that are expected to be amortized into earnings through 2037. Derivative Financial Statement Presentation and Amounts At June 30, 2015 , the fair value of energy-related derivatives and interest rate derivatives was reflected in the balance sheets as follows: Asset Derivatives at June 30, 2015 Fair Value Derivative Category and Balance Sheet Location Southern Company Alabama Power Georgia Power Gulf Power Mississippi Power Southern Power (in millions) Derivatives designated as hedging instruments for regulatory purposes Energy-related derivatives: Other current assets $ 5 $ 2 $ 3 $ — $ — N/A Derivatives designated as hedging instruments in cash flow and fair value hedges Interest rate derivatives: Other current assets $ 11 $ — $ 5 $ — $ — $ — Total asset derivatives $ 16 $ 2 $ 8 $ — $ — $ — Liability Derivatives at June 30, 2015 Fair Value Derivative Category and Balance Sheet Location Southern Company Alabama Power Georgia Power Gulf Power Mississippi Power Southern Power (in millions) Derivatives designated as hedging instruments for regulatory purposes Energy-related derivatives: Other current liabilities (*) $ 99 $ 31 $ 15 $ 32 $ 21 Other deferred credits and liabilities 81 17 2 42 20 Total derivatives designated as hedging instruments for regulatory purposes $ 180 $ 48 $ 17 $ 74 $ 41 N/A Derivatives designated as hedging instruments in cash flow and fair value hedges Interest rate derivatives: Other current liabilities (*) $ 8 $ 7 $ 1 $ — $ — $ — Other deferred credits and liabilities 6 — 3 — — — Total derivatives designed as hedging instruments in cash flow and fair value hedges $ 14 $ 7 $ 4 $ — $ — $ — Total liability derivatives $ 194 $ 55 $ 21 $ 74 $ 41 $ — (*) Gulf Power includes current liabilities related to derivatives designated as hedging instruments in "Liabilities from risk management activities." At December 31, 2014 , the fair value of energy-related derivatives and interest rate derivatives was reflected in the balance sheets as follows: Asset Derivatives at December 31, 2014 Fair Value Derivative Category and Balance Sheet Location Southern Company Alabama Power Georgia Power Gulf Power Mississippi Power Southern Power (in millions) Derivatives designated as hedging instruments for regulatory purposes Energy-related derivatives: Other current assets $ 7 $ 1 $ 6 $ — $ — Other deferred charges and assets — — 1 — — Total derivatives designated as hedging instruments for regulatory purposes $ 7 $ 1 $ 7 $ — $ — N/A Derivatives designated as hedging instruments in cash flow and fair value hedges Interest rate derivatives: Other current assets $ 7 $ — $ 5 $ — $ — $ — Other deferred charges and assets 1 — 1 — — — Total derivatives designated as hedging instruments in cash flow and fair value hedges $ 8 $ — $ 6 $ — $ — $ — Derivatives not designated as hedging instruments Energy-related derivatives: Other current assets $ 6 $ — $ — $ — $ — $ 5 Total asset derivatives $ 21 $ 1 $ 13 $ — $ — $ 5 Liability Derivatives at December 31, 2014 Fair Value Derivative Category and Balance Sheet Location Southern Company Alabama Power Georgia Power Gulf Power Mississippi Power Southern Power (in millions) Derivatives designated as hedging instruments for regulatory purposes Energy-related derivatives: Other current liabilities (*) $ 118 $ 32 $ 23 $ 37 $ 26 Other deferred credits and liabilities 79 21 4 35 19 Total derivatives designated as hedging instruments for regulatory purposes $ 197 $ 53 $ 27 $ 72 $ 45 N/A Derivatives designated as hedging instruments in cash flow and fair value hedges Interest rate derivatives: Other current liabilities (*) $ 17 $ 8 $ 9 $ — $ — $ — Other deferred credits and liabilities 7 — 5 — — — Total derivatives designated as hedging instruments in cash flow and fair value hedges $ 24 $ 8 $ 14 $ — $ — $ — Derivatives not designated as hedging instruments Energy-related derivatives: Other current liabilities $ 4 $ — $ — $ — $ — $ 4 Total liability derivatives $ 225 $ 61 $ 41 $ 72 $ 45 $ 4 (*) Gulf Power includes current liabilities related to derivatives designated as hedging instruments in "Liabilities from risk management activities." The derivative contracts of Southern Company, the traditional operating companies, and Southern Power are not subject to master netting arrangements or similar agreements and are reported gross on each registrant's financial statements. Some of these energy-related and interest rate derivative contracts may contain certain provisions that permit intra-contract netting of derivative receivables and payables for routine billing and offsets related to events of default and settlements. Amounts related to energy-related derivative contracts and interest rate derivative contracts at June 30, 2015 and December 31, 2014 are presented in the following tables. Derivative Contracts at June 30, 2015 Fair Value Southern Company Alabama Power Georgia Power Gulf Power Mississippi Power Southern Power (in millions) Assets Energy-related derivatives: Energy-related derivatives presented in the Balance Sheet (a) $ 5 $ 2 $ 3 $ — $ — $ — Gross amounts not offset in the Balance Sheet (b) (5 ) (2 ) (3 ) — — — Net energy-related derivative assets $ — $ — $ — $ — $ — $ — Interest rate derivatives: Interest rate derivatives presented in the Balance Sheet (a) $ 11 $ — $ 5 $ — $ — $ — Gross amounts not offset in the Balance Sheet (b) (8 ) — (3 ) — — — Net interest rate derivative assets $ 3 $ — $ 2 $ — $ — $ — Liabilities Energy-related derivatives: Energy-related derivatives presented in the Balance Sheet (a) $ 180 $ 48 $ 17 $ 74 $ 41 $ — Gross amounts not offset in the Balance Sheet (b) (5 ) (2 ) (3 ) — — — Net energy-related derivative liabilities $ 175 $ 46 $ 14 $ 74 $ 41 $ — Interest rate derivatives: Interest rate derivatives presented in the Balance Sheet (a) $ 14 $ 7 $ 4 $ — $ — $ — Gross amounts not offset in the Balance Sheet (b) (8 ) — (3 ) — — — Net interest rate derivative liabilities $ 6 $ 7 $ 1 $ — $ — $ — (a) None of the registrants offsets fair value amounts for multiple derivative instruments executed with the same counterparty on the balance sheets; therefore, gross and net amounts of derivative assets and liabilities presented on the balance sheets are the same. (b) Includes gross amounts subject to netting terms that are not offset on the balance sheets and any cash/financial collateral pledged or received. Derivative Contracts at December 31, 2014 Fair Value Southern Company Alabama Power Georgia Power Gulf Power Mississippi Power Southern Power (in millions) Assets Energy-related derivatives: Energy-related derivatives presented in the Balance Sheet (a) $ 13 $ 1 $ 7 $ — $ — $ 5 Gross amounts not offset in the Balance Sheet (b) (9 ) — (7 ) — — — Net energy-related derivative assets $ 4 $ 1 $ — $ — $ — $ 5 Interest rate derivatives: Interest rate derivatives presented in the Balance Sheet (a) $ 8 $ — $ 6 $ — $ — $ — Gross amounts not offset in the Balance Sheet (b) (8 ) — (6 ) — — — Net interest rate derivative assets $ — $ — $ — $ — $ — $ — Liabilities Energy-related derivatives: Energy-related derivatives presented in the Balance Sheet (a) $ 201 $ 53 $ 27 $ 72 $ 45 $ 4 Gross amounts not offset in the Balance Sheet (b) (9 ) — (7 ) — — — Net energy-related derivative liabilities $ 192 $ 53 $ 20 $ 72 $ 45 $ 4 Interest rate derivatives: Interest rate derivatives presented in the Balance Sheet (a) $ 24 $ 8 $ 14 $ — $ — $ — Gross amounts not offset in the Balance Sheet (b) (8 ) — (6 ) — — — Net interest rate derivative liabilities $ 16 $ 8 $ 8 $ — $ — $ — (a) None of the registrants offsets fair value amounts for multiple derivative instruments executed with the same counterparty on the balance sheets; therefore, gross and net amounts of derivative assets and liabilities presented on the balance sheets are the same. (b) Includes gross amounts subject to netting terms that are not offset on the balance sheets and any cash/financial collateral pledged or received. At June 30, 2015 and December 31, 2014 , the pre-tax effects of unrealized derivative gains (losses) arising from energy-related derivative instruments designated as regulatory hedging instruments and deferred were as follows: Regulatory Hedge Unrealized Gain (Loss) Recognized on the Balance Sheet at June 30, 2015 Derivative Category and Balance Sheet Location Southern Company Alabama Power Georgia Power Gulf Power Mississippi Power (in millions) Energy-related derivatives: Other regulatory assets, current $ (99 ) $ (31 ) $ (15 ) $ (32 ) $ (21 ) Other regulatory assets, deferred (81 ) (17 ) (2 ) (42 ) (20 ) Other regulatory liabilities, current (a) 5 2 3 — — Other regulatory liabilities, deferred (b) — — — — — Total energy-related derivative gains (losses) $ (175 ) $ (46 ) $ (14 ) $ (74 ) $ (41 ) (a) Southern Company, Alabama Power, and Georgia Power include other regulatory liabilities, current in other current liabilities. (b) Georgia Power includes other regulatory liabilities, deferred in other deferred credits and liabilities. Regulatory Hedge Unrealized Gain (Loss) Recognized on the Balance Sheet at December 31, 2014 Derivative Category and Balance Sheet Location Southern Company Alabama Power Georgia Power Gulf Power Mississippi Power (in millions) Energy-related derivatives: Other regulatory assets, current $ (118 ) $ (32 ) $ (23 ) $ (37 ) $ (26 ) Other regulatory assets, deferred (79 ) (21 ) (4 ) (35 ) (19 ) Other regulatory liabilities, current (a) 7 1 6 — — Other regulatory liabilities, deferred (b) — — 1 — — Total energy-related derivative gains (losses) $ (190 ) $ (52 ) $ (20 ) $ (72 ) $ (45 ) (a) Southern Company, Alabama Power, and Georgia Power include other regulatory liabilities, current in other current liabilities. (b) Georgia Power includes other regulatory liabilities, deferred in other deferred credits and liabilities. For the three months ended June 30, 2015 and 2014 , the pre-tax effects of interest rate derivatives designated as cash flow hedging instruments on the statements of income were as follows: Derivatives in Cash Flow Hedging Relationships Gain (Loss) Recognized in OCI on Derivative (Effective Portion) Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion) Statements of Income Location Amount 2015 2014 2015 2014 (in millions) (in millions) Southern Company Interest rate derivatives $ 31 $ — Interest expense, net of amounts capitalized $ (2 ) $ (2 ) Alabama Power Interest rate derivatives $ 7 $ — Interest expense, net of amounts capitalized $ (1 ) $ — Georgia Power Interest rate derivatives $ 24 $ — Interest expense, net of amounts capitalized $ (1 ) $ — Mississippi Power Interest rate derivatives $ — $ — Interest expense, net of amounts capitalized $ — $ (1 ) Southern Power Interest rate derivatives $ — $ — Interest expense, net of amounts capitalized $ — $ (1 ) For the six months ended June 30, 2015 and 2014 , the pre-tax effects of interest rate derivatives designated as cash flow hedging instruments recognized in OCI and those reclassified from accumulated OCI into earnings were immaterial for all registrants. For the three and six months ended June 30, 2015 and 2014 , the pre-tax effects of energy-related derivatives designated as cash flow hedging instruments recognized in OCI and those reclassified from accumulated OCI into earnings were immaterial for all registrants. For the three and six months ended June 30, 2015 and 2014 , the pre-tax effects of interest rate derivatives designated as fair value hedging instruments were immaterial on a gross basis for all registrants. Furthermore, the pre-tax effects of interest rate derivatives designated as fair value hedging instruments were offset by changes to the carrying value of long-term debt. There was no material ineffectiveness recorded in earnings for any registrant for any period presented. For the three and six months ended June 30, 2015 and 2014 , the pre-tax effects of energy-related derivatives not designated as hedging instruments were immaterial for all registrants. Contingent Features The registrants do not have any credit arrangements that would require material changes in payment schedules or terminations as a result of a credit rating downgrade. There are certain derivatives that could require collateral, but not accelerated payment, in the event of various credit rating changes of certain Southern Company subsidiaries. At June 30, 2015 , the registrants' collateral posted with their derivative counterparties was immaterial. At June 30, 2015 , the fair value of derivative liabilities with contingent features was $49 million for all registrants. The maximum potential collateral requirements arising from the credit-risk-related contingent features, at a rating below BBB- and/or Baa3, were $49 million and include certain agreements that could require collateral in the event that one or more Southern Company power pool participants has a credit rating change to below investment grade. Generally, collateral may be provided by a Southern Company guaranty, letter of credit, or cash. If collateral is required, fair value amounts recognized for the right to reclaim cash collateral or the obligation to return cash collateral are not offset against fair value amounts recognized for derivatives executed with the same counterparty. Southern Company, the traditional operating companies, and Southern Power are exposed to losses related to financial instruments in the event of counterparties' nonperformance. Southern Company, the traditional operating companies, and Southern Power only enter into agreements and material transactions with counterparties that have investment grade credit ratings by Moody's and S&P or with counterparties who have posted collateral to cover potential credit exposure. Southern Company, the traditional operating companies, and Southern Power have also established risk management policies and controls to determine and monitor the creditworthiness of counterparties in order to mitigate Southern Company's, the traditional operating companies', and Southern Power's exposure to counterparty credit risk. Therefore, Southern Company, the traditional operating companies, and Southern Power do not anticipate a material adverse effect on the financial statements as a result of counterparty nonperformance.

Acquisitions

Acquisitions	6 Months Ended
	Jun. 30, 2015
Business Combinations [Abstract]
ACQUISITIONS	ACQUISITIONS See Note 2 to the financial statements of Southern Power under "2014 – SG2 Imperial Valley, LLC" in Item 8 of the Form 10-K for additional information. During the second quarter 2015, the fair values of the assets acquired of SG2 Imperial Valley, LLC were finalized and recorded as follows: $707 million as property, plant, and equipment and $20 million as prepayments related to transmission services. During 2015, Southern Power Company acquired or contracted to acquire the following projects in accordance with its overall growth strategy. Acquisition-related costs were expensed as incurred and were not material. Kay County Wind Facility On February 24, 2015, Southern Power Company, through its wholly-owned subsidiary Southern Renewable Energy, Inc., entered into a purchase agreement with Kay Wind Holdings, LLC, a wholly-owned subsidiary of Apex Clean Energy Holdings, LLC, the developer of the project, to acquire all of the outstanding membership interests of Kay Wind, LLC (Kay Wind) for approximately $492 million , with potential purchase price adjustments based on performance testing. Kay Wind is constructing and owns an approximately 299 -MW wind facility in Kay County, Oklahoma. The wind facility is expected to begin commercial operation in late 2015 , and the entire output of the facility is contracted under separate 20 -year PPAs with Westar Energy, Inc. and Grand River Dam Authority. The completion of the acquisition is subject to Kay Wind achieving certain construction and project milestones, as well as various other customary conditions to closing, and is expected to close in the fourth quarter 2015. The ultimate outcome of this matter cannot be determined at this time. Lost Hills-Blackwell Solar Facilities On April 15, 2015, Southern Power Company, through its subsidiary Southern Renewable Partnerships, LLC (SRP), acquired 100% of the class A membership interests of Lost Hills Blackwell Holdings, LLC (Lost Hills Blackwell) from a wholly-owned subsidiary of First Solar, Inc. (First Solar), the developer of the project, for approximately $74 million . Concurrently, a wholly-owned subsidiary of First Solar acquired 100% of the class B membership interests of Lost Hills Blackwell for approximately $33 million . SRP and the class B member are entitled to 51% and 49% , respectively, of all cash distributions from Lost Hills Blackwell. In addition, Southern Power Company is entitled to substantially all of the federal tax benefits with respect to the transaction. Lost Hills Blackwell constructed and owns the approximately 22 -MW Lost Hills and the approximately 13 -MW Blackwell solar facilities in Kern County, California. These solar facilities began commercial operation on April 17, 2015 , and their entire output is contracted under PPAs, initially to the City of Roseville, California and then to Pacific Gas and Electric Company, that together extend approximately 29 years. As of June 30, 2015, the fair values of the assets acquired were recorded as follows: $98 million as property, plant, and equipment and $9 million as a receivable related to transmission interconnection costs; however, the allocation of the purchase price to individual assets has not been finalized. The acquisition did not include any contingent consideration. North Star Solar Facility On April 30, 2015, Southern Power Company, through its subsidiary SRP, acquired 100% of the class A membership interests of NS Solar Holdings, LLC (North Star) from a wholly-owned subsidiary of First Solar, the developer of the project, for approximately $211 million . Concurrently, a wholly-owned subsidiary of First Solar acquired 100% of the class B membership interests of North Star for approximately $100 million . SRP and the class B member are entitled to 51% and 49% , respectively, of all cash distributions from North Star. In addition, Southern Power Company is entitled to substantially all of the federal tax benefits with respect to the transaction. North Star constructed and owns the approximately 61 -MW North Star solar facility in Fresno County, California. The solar facility began commercial operation on June 20, 2015, and the entire output of the project is contracted under a 20 -year PPA with Pacific Gas and Electric Company. As of June 30, 2015, the fair values of the assets acquired were recorded as follows: $266 million as property, plant, and equipment, $24 million as an intangible asset, and $21 million as a receivable related to transmission interconnection costs; however, the allocation of the purchase price to individual assets has not been finalized. The acquisition did not include any contingent consideration. Construction Projects In December 2014, Southern Power Company announced plans to build a solar photovoltaic facility, and during 2015, Southern Power Company acquired all the outstanding membership interests of five separate solar project development entities. The construction projects are in accordance with Southern Power's overall growth strategy and included in its capital program estimates for 2015. The total cost of construction incurred for these projects through June 30, 2015 was $188 million . The ultimate outcome of these matters cannot be determined at this time. Southern Power Company's construction projects are detailed in the table below: Solar Project Seller Nameplate Capacity County Location in Georgia Expected Commercial Operation Date PPA Counterparty for Entire Plant Output PPA Contract Period Estimated Construction Cost (MW) (in millions) Taylor County N/A 146 Taylor Fourth quarter 2016 Cobb, Flint, and Sawnee Electric Membership Corporations 25 years $ 260 - $280 Decatur Parkway TradeWind Energy, Inc. 84 Decatur December 2015 Georgia Power (a) 25 years $ 170 - $173 (b) Decatur County TradeWind Energy, Inc. 20 Decatur December 2015 Georgia Power (a) 20 years $ 45 - $47 (b) Butler CERSM, LLC and Community Energy, Inc. 103 Taylor December 2016 Georgia Power (a) 30 years $ 220 - $230 (b) Pawpaw Longview Solar, LLC 30 Taylor December 2015 Georgia Power (a) 30 years $ 70 - $80 (b) Butler Solar Farm Strata Solar Development, LLC 20 Taylor December 2015 Georgia Power (a) 20 years $ 42 - $48 (b) (a) Subject to FERC approval. (b) Includes the acquisition price of all outstanding membership interests.

Segment and Related Information

Segment and Related Information	6 Months Ended
	Jun. 30, 2015
Segment Reporting [Abstract]
SEGMENT AND RELATED INFORMATION	SEGMENT AND RELATED INFORMATION The primary business of the Southern Company system is electricity sales by the traditional operating companies and Southern Power. The four traditional operating companies – Alabama Power, Georgia Power, Gulf Power, and Mississippi Power – are vertically integrated utilities providing electric service in four Southeastern states. Southern Power constructs, acquires, owns, and manages generation assets, including renewable energy projects, and sells electricity at market-based rates in the wholesale market. Southern Company's reportable business segments are the sale of electricity by the four traditional operating companies and Southern Power. Revenues from sales by Southern Power to the traditional operating companies were $85 million and $199 million for the three and six months ended June 30, 2015 , respectively, and $68 million and $140 million for the three and six months ended June 30, 2014 , respectively. The "All Other" column includes parent Southern Company, which does not allocate operating expenses to business segments. Also, this category includes segments below the quantitative threshold for separate disclosure. These segments include investments in telecommunications and leveraged lease projects. All other inter-segment revenues are not material. Financial data for business segments and products and services for the three and six months ended June 30, 2015 and 2014 was as follows: Electric Utilities Traditional Operating Companies Southern Power Eliminations Total All Other Eliminations Consolidated (in millions) Three Months Ended June 30, 2015: Operating revenues $ 4,077 $ 337 $ (90 ) $ 4,324 $ 43 $ (30 ) $ 4,337 Segment net income (loss) (a)(b) 561 46 — 607 18 4 629 Six Months Ended June 30, 2015: Operating revenues $ 8,025 $ 684 $ (213 ) $ 8,496 $ 83 $ (59 ) $ 8,520 Segment net income (loss) (a)(c) 1,038 79 — 1,117 21 — 1,138 Total assets at June 30, 2015 $ 67,362 $ 6,226 $ (277 ) $ 73,311 $ 1,360 $ (490 ) $ 74,181 Three Months Ended June 30, 2014: Operating revenues $ 4,209 $ 329 $ (84 ) $ 4,454 $ 39 $ (26 ) $ 4,467 Segment net income (loss) (a) 580 31 — 611 2 (2 ) 611 Six Months Ended June 30, 2014: Operating revenues $ 8,587 $ 680 $ (186 ) $ 9,081 $ 80 $ (50 ) $ 9,111 Segment net income (loss) (a)(c) 899 64 — 963 2 (3 ) 962 Total assets at December 31, 2014 $ 64,644 $ 5,550 $ (131 ) $ 70,063 $ 1,156 $ (296 ) $ 70,923 (a) After dividends on preferred and preference stock of subsidiaries. (b) Segment net income (loss) for the traditional operating companies for the three months ended June 30, 2015 includes a $23 million pre-tax charge ( $14 million after tax) for estimated probable losses on the Kemper IGCC. See Note (B) under "Integrated Coal Gasification Combined Cycle – Kemper IGCC Schedule and Cost Estimate" herein for additional information. (c) Segment net income (loss) for the traditional operating companies for the six months ended June 30, 2015 and June 30, 2014 includes a $32 million pre-tax charge ( $20 million after tax) and a $380 million pre-tax charge ( $235 million after tax), respectively, for estimated probable losses on the Kemper IGCC. See Note (B) under "Integrated Coal Gasification Combined Cycle – Kemper IGCC Schedule and Cost Estimate" herein for additional information. Products and Services Electric Utilities' Revenues Period Retail Wholesale Other Total (in millions) Three Months Ended June 30, 2015 $ 3,714 $ 448 $ 162 $ 4,324 Three Months Ended June 30, 2014 3,770 515 169 4,454 Six Months Ended June 30, 2015 $ 7,256 $ 915 $ 325 $ 8,496 Six Months Ended June 30, 2014 7,628 1,119 334 9,081

Introduction (Policies)

Introduction (Policies)	6 Months Ended
	Jun. 30, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Reclassification	Certain prior year data presented in the financial statements have been reclassified to conform to the current year presentation. These reclassifications had no impact on the results of operations, financial position, or cash flows of any registrant.
Recently Issued Accounting Standards	Recently Issued Accounting Standards The Financial Accounting Standards Board's (FASB) ASC 606, Revenue from Contracts with Customers , revises the accounting for revenue recognition effective for fiscal years beginning after December 15, 2017. The registrants continue to evaluate the requirements of ASC 606. The ultimate impact of the new standard has not yet been determined. On February 18, 2015, the FASB issued Accounting Standards Update (ASU) 2015-02, Amendments to the Consolidation Analysis , which makes certain changes to both the variable interest model and the voting model, including changes to the identification of variable interests, the variable interest entity characteristics for a limited partnership or similar entity, and the primary beneficiary determination. This ASU is effective for fiscal years beginning after December 15, 2015. Southern Power is currently evaluating these requirements. The ultimate impact of this ASU on Southern Power has not yet been determined. On April 7, 2015, the FASB issued ASU No. 2015-03, Interest – Imputation of Interest (Subtopic 835-30): Simplifying the Presentation of Debt Issuance Costs . The ASU requires that debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability and is effective for fiscal years beginning after December 15, 2015. Southern Company currently reflects unamortized debt issuance costs in unamortized debt issuance expense on its balance sheet. The traditional operating companies and Southern Power currently reflect unamortized debt issuance costs in other deferred charges and assets on their balance sheets. Upon adoption, the reclassification will not have a material impact on the results of operations, financial position, or cash flows of any registrant.
Valuation Methodologies	Valuation Methodologies The energy-related derivatives primarily consist of over-the-counter financial products for natural gas and physical power products, including, from time to time, basis swaps. These are standard products used within the energy industry and are valued using the market approach. The inputs used are mainly from observable market sources, such as forward natural gas prices, power prices, implied volatility, and overnight index swap interest rates. Interest rate derivatives are also standard over-the-counter financial products valued using the market approach. Inputs for interest rate derivatives include LIBOR interest rates, interest rate futures contracts, and occasionally, implied volatility of interest rate options. See Note (H) herein for additional information on how these derivatives are used. For fair value measurements of the investments within the nuclear decommissioning trusts, external pricing vendors are designated for each asset class with each security specifically assigned a primary pricing source. For investments held within commingled funds, fair value is determined at the end of each business day through the net asset value, which is established by obtaining the underlying securities' individual prices from the primary pricing source. A market price secured from the primary source vendor is then evaluated by management in its valuation of the assets within the trusts. As a general approach, fixed income market pricing vendors gather market data (including indices and market research reports) and integrate relative credit information, observed market movements, and sector news into proprietary pricing models, pricing systems, and mathematical tools. Dealer quotes and other market information, including live trading levels and pricing analysts' judgment, are also obtained when available. Investments in private equity and real estate within Alabama Power's nuclear decommissioning trusts are generally classified as Level 3, as the underlying assets typically do not have observable inputs. The fund manager values these assets using various inputs and techniques depending on the nature of the underlying investments. The fair value of partnerships is determined by aggregating the value of the underlying assets. "Other investments" include investments that are not traded in the open market. The fair value of these investments have been determined based on market factors including comparable multiples and the expectations regarding cash flows and business plan executions.
Earnings per Share	Earnings per Share For Southern Company, the only difference in computing basic and diluted earnings per share is attributable to awards outstanding under the stock option and performance share plans. See Note 8 to the financial statements of Southern Company in Item 8 of the Form 10-K for information on the stock option and performance share plans. The effect of both stock options and performance share award units was determined using the treasury stock method.
Energy-Related Derivatives and Interest Rate Derivatives	Energy-Related Derivatives The traditional operating companies and Southern Power enter into energy-related derivatives to hedge exposures to electricity, gas, and other fuel price changes. However, due to cost-based rate regulations and other various cost recovery mechanisms, the traditional operating companies have limited exposure to market volatility in commodity fuel prices and prices of electricity. Each of the traditional operating companies manages fuel-hedging programs, implemented per the guidelines of their respective state PSCs, through the use of financial derivative contracts, which is expected to continue to mitigate price volatility. The traditional operating companies (with respect to wholesale generating capacity) and Southern Power have limited exposure to market volatility in commodity fuel prices and prices of electricity because their long-term sales contracts shift substantially all fuel cost responsibility to the purchaser. However, the traditional operating companies and Southern Power may be exposed to market volatility in energy-related commodity prices to the extent any uncontracted wholesale generating capacity is used to sell electricity. To mitigate residual risks relative to movements in electricity prices, the traditional operating companies and Southern Power may enter into physical fixed-price contracts for the purchase and sale of electricity through the wholesale electricity market. To mitigate residual risks relative to movements in gas prices, the traditional operating companies and Southern Power may enter into fixed-price contracts for natural gas purchases; however, a significant portion of contracts are priced at market. Energy-related derivative contracts are accounted for under one of three methods: • Regulatory Hedges — Energy-related derivative contracts which are designated as regulatory hedges relate primarily to the traditional operating companies' fuel-hedging programs, where gains and losses are initially recorded as regulatory liabilities and assets, respectively, and then are included in fuel expense as the underlying fuel is used in operations and ultimately recovered through the respective fuel cost recovery clauses. • Cash Flow Hedges — Gains and losses on energy-related derivatives designated as cash flow hedges which are mainly used to hedge anticipated purchases and sales and are initially deferred in OCI before being recognized in the statements of income in the same period as the hedged transactions are reflected in earnings. • Not Designated — Gains and losses on energy-related derivative contracts that are not designated or fail to qualify as hedges are recognized in the statements of income as incurred. Some energy-related derivative contracts require physical delivery as opposed to financial settlement, and this type of derivative is both common and prevalent within the electric industry. When an energy-related derivative contract is settled physically, any cumulative unrealized gain or loss is reversed and the contract price is recognized in the respective line item representing the actual price of the underlying goods being delivered. Interest Rate Derivatives Southern Company and certain subsidiaries may also enter into interest rate derivatives to hedge exposure to changes in interest rates. The derivatives employed as hedging instruments are structured to minimize ineffectiveness. Derivatives related to existing variable rate securities or forecasted transactions are accounted for as cash flow hedges where the effective portion of the derivatives' fair value gains or losses is recorded in OCI and is reclassified into earnings at the same time the hedged transactions affect earnings, with any ineffectiveness recorded directly to earnings. Derivatives related to existing fixed rate securities are accounted for as fair value hedges, where the derivatives' fair value gains or losses and hedged items' fair value gains or losses are both recorded directly to earnings, providing an offset, with any difference representing ineffectiveness.

Introduction (Tables)

Introduction (Tables)	6 Months Ended
	Jun. 30, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Schedule of Asset Retirement Obligations	As of June 30, 2015 , details of the AROs, including those related to the CCR Rule, included in Southern Company's and the traditional operating companies' Condensed Balance Sheets herein were as follows: Southern Company Alabama Power Georgia Power Gulf Power Mississippi Power (in millions) Balance at beginning of year $ 2,201 $ 829 $ 1,255 $ 17 $ 48 Liabilities incurred 612 401 — 71 97 Liabilities settled (10 ) (1 ) (9 ) — — Accretion 53 23 28 — 1 Cash flow revisions 58 — 82 4 2 Balance at end of period $ 2,914 $ 1,252 $ 1,356 $ 92 $ 148

Contingencies and Regulatory 21

Contingencies and Regulatory Matters (Tables)	6 Months Ended
	Jun. 30, 2015
Commitments and Contingencies Disclosure [Abstract]
Schedule of Recovery Balance of Each Regulatory Clause	The recovery balance of each regulatory clause follows: Regulatory Clause Balance Sheet Line Item June 30, 2015 December 31, 2014 (in millions) Rate CNP Compliance – Under * Deferred under recovered regulatory clause revenues $ 25 $ 2 Under recovered regulatory clause revenues, current 29 47 Rate CNP PPA – Under Deferred under recovered regulatory clause revenues 72 29 Under recovered regulatory clause revenues, current — 27 Retail Energy Cost Recovery – Over Deferred over recovered regulatory clause revenues 72 47 Natural Disaster Reserve Other regulatory liabilities, deferred 81 84 * Formerly Known As Rate CNP Environmental
Recovery Position of Each Regulatory Clause	The recovery balance of each regulatory clause follows: Recovery Clause Balance Sheet Location June 30, 2015 December 31, 2014 (in millions) Fuel Cost Recovery – Under Under recovered regulatory clause revenues $ 24 $ 40 Purchased Power Capacity Recovery – Under Under recovered regulatory clause revenues 2 — Environmental Cost Recovery – Under Under recovered regulatory clause revenues 7 10 Energy Conservation Cost Recovery – Under Under recovered regulatory clause revenues — 3
Current And Actual Cost Estimate for Kemper IGCC	Mississippi Power's Kemper IGCC 2010 project estimate, current cost estimate (which includes the impacts of the Mississippi Supreme Court's (Court) decision), and actual costs incurred as of June 30, 2015 , as adjusted for the Court's decision, are as follows: Cost Category 2010 Project Estimate (f) Current Estimate Actual Costs at June 30, 2015 (in billions) Plant Subject to Cost Cap (a) $ 2.40 $ 4.96 $ 4.51 Lignite Mine and Equipment 0.21 0.23 0.23 CO 2 Pipeline Facilities 0.14 0.11 0.11 AFUDC (b)(c) 0.17 0.62 0.52 Combined Cycle and Related Assets Placed in (d) — 0.02 — General Exceptions 0.05 0.10 0.08 Deferred Costs (c)(e) — 0.19 0.15 Total Kemper IGCC (a)(c) $ 2.97 $ 6.23 $ 5.60 (a) 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. The Current Estimate and Actual Costs include non-incremental operating and maintenance costs related to the combined cycle and associated common facilities placed in service in August 2014 that are subject to the $2.88 billion cost cap and exclude post-in-service costs for the lignite mine. See "Rate Recovery of Kemper IGCC Costs – 2013 MPSC Rate Order" for additional information. The Current Estimate and Actual Costs include the 15% undivided interest in the Kemper IGCC that was previously projected to be purchased by SMEPA. On May 20, 2015, SMEPA notified Mississippi Power of its termination of the asset purchase agreement (APA) and requested the return of a total of $275 million of deposits, which was returned with accrued interest on June 3, 2015. (b) Mississippi Power's original estimate included recovery of financing costs during construction rather than the accrual of AFUDC. This approach was not approved by the Mississippi PSC in 2012 as described in "Rate Recovery of Kemper IGCC Costs." The current estimate includes an approximately $11 million decrease in AFUDC due to a decrease in AFUDC rates resulting from an increase in short-term debt, partially offset by an $8 million increase in AFUDC related to a settlement agreement with the wholesale customers for cost-based rates under FERC's jurisdiction. See "FERC Matters" herein for additional information. (c) Amounts in the Current Estimate reflect estimated costs through March 31, 2016. (d) Incremental operating and maintenance costs related to the combined cycle and associated common facilities placed in service in August 2014, net of costs related to energy sales. See "Rate Recovery of Kemper IGCC Costs – 2013 MPSC Rate Order" for additional information. (e) The 2012 MPSC CPCN Order approved deferral of non-capital Kemper IGCC-related costs during construction as described in "Rate Recovery of Kemper IGCC Costs – Regulatory Assets and Liabilities." (f) The 2010 Project Estimate is the certificated cost estimate adjusted to include the certificated estimate for the CO 2 pipeline facilities which was approved in 2011 by the Mississippi PSC.

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	6 Months Ended
	Jun. 30, 2015
Fair Value Disclosures [Abstract]
Assets and liabilities measured at fair value on a recurring basis	As of June 30, 2015 , assets and liabilities measured at fair value on a recurring basis during the period, together with the associated level of the fair value hierarchy, were as follows: Fair Value Measurements Using As of June 30, 2015: Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Total (in millions) Southern Company Assets: Energy-related derivatives $ — $ 5 $ — $ 5 Interest rate derivatives — 11 — 11 Nuclear decommissioning trusts (a) 677 887 7 1,571 Cash equivalents 533 — — 533 Other investments 9 — 1 10 Total $ 1,219 $ 903 $ 8 $ 2,130 Liabilities: Energy-related derivatives $ — $ 180 $ — $ 180 Interest rate derivatives — 14 — 14 Total $ — $ 194 $ — $ 194 Alabama Power Assets: Energy-related derivatives $ — $ 2 $ — $ 2 Nuclear decommissioning trusts (b) Domestic equity 381 78 — 459 Foreign equity 51 50 — 101 U.S. Treasury and government agency securities — 36 — 36 Corporate bonds 10 121 — 131 Mortgage and asset backed securities — 17 — 17 Other — 6 7 13 Cash equivalents 81 — — 81 Total $ 523 $ 310 $ 7 $ 840 Liabilities: Energy-related derivatives $ — $ 48 $ — $ 48 Interest rate derivatives — 7 — 7 Total $ — $ 55 $ — $ 55 Fair Value Measurements Using As of June 30, 2015: Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Total (in millions) Georgia Power Assets: Energy-related derivatives $ — $ 3 $ — $ 3 Interest rate derivatives — 5 — 5 Nuclear decommissioning trusts (b) (c) Domestic equity 182 1 — 183 Foreign equity — 125 — 125 U.S. Treasury and government agency securities — 95 — 95 Municipal bonds — 78 — 78 Corporate bonds — 169 — 169 Mortgage and asset backed securities — 108 — 108 Other 53 3 — 56 Total $ 235 $ 587 $ — $ 822 Liabilities: Energy-related derivatives $ — $ 17 $ — $ 17 Interest rate derivatives — 4 — 4 Total $ — $ 21 $ — $ 21 Gulf Power Assets: Cash equivalents $ 18 $ — $ — $ 18 Liabilities: Energy-related derivatives — 74 — 74 Mississippi Power Assets: Cash equivalents $ 182 $ — $ — $ 182 Liabilities: Energy-related derivatives — 41 — 41 Southern Power Assets: Cash equivalents $ 206 $ — $ — $ 206 (a) For additional detail, see the nuclear decommissioning trusts sections for Alabama Power and Georgia Power in this table. (b) Excludes receivables related to investment income, pending investment sales, payables related to pending investment purchases, and currencies. (c) Includes the investment securities pledged to creditors and collateral received and excludes payables related to the securities lending program. As of June 30, 2015 , approximately $39 million of the fair market value of Georgia Power's nuclear decommissioning trust funds' securities were on loan to creditors under the funds' managers' securities lending program.
Fair value measurements of investments calculated at net asset value per share as well as the nature and risk of those investments	As of June 30, 2015 , the fair value measurements of investments calculated at net asset value per share (or its equivalent), as well as the nature and risks of those investments, were as follows: As of June 30, 2015: Fair Value Unfunded Commitments Redemption Frequency Redemption Notice Period (in millions) Southern Company Nuclear decommissioning trusts: Foreign equity funds $ 125 None Monthly 5 days Equity - commingled funds 50 None Daily Daily Debt - commingled funds 16 None Daily 5 days Other - commingled funds 3 None Daily Not applicable Other - money market funds 53 None Daily Not applicable Trust-owned life insurance 117 None Daily 15 days Cash equivalents: Money market funds 533 None Daily Not applicable Alabama Power Nuclear decommissioning trusts: Equity - commingled funds $ 50 None Daily Daily Debt - commingled funds 16 None Daily 5 days Trust-owned life insurance 117 None Daily 15 days Cash equivalents: Money market funds 81 None Daily Not applicable Georgia Power Nuclear decommissioning trusts: Foreign equity funds $ 125 None Monthly 5 days Other - commingled funds 3 None Daily Not applicable Other - money market funds 53 None Daily Not applicable Gulf Power Cash equivalents: Money market funds $ 18 None Daily Not applicable Mississippi Power Cash equivalents: Money market funds $ 182 None Daily Not applicable Southern Power Cash equivalents: Money market funds $ 206 None Daily Not applicable
Financial instruments for which carrying amount did not equal fair value	As of June 30, 2015 , other financial instruments for which the carrying amount did not equal fair value were as follows: Carrying Amount Fair Value (in millions) Long-term debt, including securities due within one year: Southern Company $ 26,156 $ 26,973 Alabama Power $ 7,295 $ 7,621 Georgia Power $ 10,379 $ 10,767 Gulf Power $ 1,370 $ 1,438 Mississippi Power $ 2,275 $ 2,246 Southern Power $ 2,262 $ 2,302

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	6 Months Ended
	Jun. 30, 2015
Equity [Abstract]
Earnings per Share	Shares used to compute diluted earnings per share were as follows: Three Months Ended June 30, 2015 Three Months Ended June 30, 2014 Six Months Ended June 30, 2015 Six Months Ended June 30, 2014 (in millions) As reported shares 909 895 910 892 Effect of options and performance share award units 3 4 4 4 Diluted shares 912 899 914 896
Changes in Stockholders' Equity	The following table presents year-to-date changes in stockholders' equity of Southern Company: Number of Common Shares Common Preferred and Preference Stock of Subsidiaries Total Issued Treasury Noncontrolling Interest (*) (in thousands) (in millions) Balance at December 31, 2014 908,502 (725 ) $ 19,949 $ 756 $ 221 $ 20,926 Net income after dividends on preferred and preference stock — — 1,138 — — 1,138 Other comprehensive income (loss) — — 7 — — 7 Stock issued 3,222 — 117 — — 117 Stock-based compensation — — 66 — — 66 Stock repurchased, at cost — (2,599 ) (115 ) — — (115 ) Cash dividends on common stock — — (972 ) — — (972 ) Preference stock redemption — — — (150 ) — (150 ) Contributions from noncontrolling interest — — — — 135 135 Distributions to noncontrolling interest — — — — (5 ) (5 ) Net income attributable to noncontrolling interest — — — — 4 4 Other — 25 (8 ) 3 — (5 ) Balance at June 30, 2015 911,724 (3,299 ) $ 20,182 $ 609 $ 355 $ 21,146 Balance at December 31, 2013 892,733 (5,647 ) $ 19,008 $ 756 $ — $ 19,764 Net income after dividends on preferred and preference stock — — 962 — — 962 Other comprehensive income (loss) — — 4 — — 4 Treasury stock re-issued — 4,739 216 — — 216 Stock issued 3,898 — 161 — — 161 Stock repurchased, at cost — — (5 ) — — (5 ) Cash dividends on common stock — — (920 ) — — (920 ) Other — (27 ) — — — — Balance at June 30, 2014 896,631 (935 ) $ 19,426 $ 756 $ — $ 20,182 (*) Primarily related to Southern Power Company.

Financing (Tables)

Financing (Tables)	6 Months Ended
	Jun. 30, 2015
Debt Disclosure [Abstract]
Credit arrangements by company	The following table outlines the committed credit arrangements by company as of June 30, 2015 : Expires Executable Term Loans Due Within One Year Company 2015 2016 2017 2018 Total Unused One Year Two Years Term Out No Term Out (in millions) (in millions) (in millions) (in millions) Southern Company $ — $ — $ — $ 1,000 $ 1,000 $ 1,000 $ — $ — $ — $ — Alabama Power 154 124 — 1,030 1,308 1,307 58 — 58 170 Georgia Power — 150 — 1,600 1,750 1,737 — — — 150 Gulf Power 20 225 30 — 275 275 50 — 50 195 Mississippi Power 40 255 — — 295 265 30 40 70 225 Southern Power — — — 500 500 466 — — — — Other 25 45 — — 70 70 20 — 20 50 Total $ 239 $ 799 $ 30 $ 4,130 $ 5,198 $ 5,120 $ 158 $ 40 $ 198 $ 790
Schedule of Long-term Debt Financing Activities	The following table outlines the long-term debt financing activities for Southern Company and its subsidiaries for the first six months of 2015 : Company (a) Senior Note Issuances Senior Note Redemptions Revenue Bond Issuances and Reofferings of Purchased Bonds (b) Revenue Other Long-Term Debt Issuances Other Long-Term Debt Redemptions and Maturities (c) (in millions) Southern Company $ 600 $ — $ — $ — $ — $ — Alabama Power 975 250 80 134 — — Georgia Power — 125 170 65 600 5 Mississippi Power — — — — — 351 Southern Power 650 — — — — — Other — — — — — 9 Total $ 2,225 $ 375 $ 250 $ 199 $ 600 $ 365 (a) Gulf Power did not issue or redeem any long-term debt during the first six months of 2015 . (b) Includes reoffering by Alabama Power of $80 million aggregate principal amount of revenue bonds previously purchased and held by Alabama Power since April 2015 and reofferings by Georgia Power of $104.6 million and $65 million aggregate principal amount of revenue bonds previously purchased and held by Georgia Power since 2013 and April 2015, respectively. (c) Includes reductions in capital lease obligations resulting from cash payments under capital leases.

Retirement Benefits (Tables)

Retirement Benefits (Tables)	6 Months Ended
	Jun. 30, 2015
Compensation and Retirement Disclosure [Abstract]
Pension Plans and Postretirement Plans	Components of the net periodic benefit costs for the three and six months ended June 30, 2015 and 2014 were as follows: Pension Plans Southern Company Alabama Power Georgia Power Gulf Power Mississippi Power (in millions) Three Months Ended June 30, 2015 Service cost $ 64 $ 15 $ 18 $ 3 $ 3 Interest cost 111 27 39 5 6 Expected return on plan assets (181 ) (44 ) (63 ) (8 ) (9 ) Amortization: Prior service costs 7 1 2 — 1 Net (gain)/loss 54 13 19 2 2 Net cost $ 55 $ 12 $ 15 $ 2 $ 3 Six Months Ended June 30, 2015 Service cost $ 128 $ 30 $ 36 $ 6 $ 6 Interest cost 222 53 77 10 11 Expected return on plan assets (362 ) (89 ) (126 ) (16 ) (17 ) Amortization: Prior service costs 13 3 5 — 1 Net (gain)/loss 108 27 38 5 5 Net cost $ 109 $ 24 $ 30 $ 5 $ 6 Three Months Ended June 30, 2014 Service cost $ 54 $ 12 $ 15 $ 1 $ 2 Interest cost 108 26 38 5 5 Expected return on plan assets (162 ) (42 ) (56 ) (7 ) (7 ) Amortization: Prior service costs 7 2 2 1 1 Net (gain)/loss 27 8 10 1 1 Net cost $ 34 $ 6 $ 9 $ 1 $ 2 Six Months Ended June 30, 2014 Service cost $ 107 $ 24 $ 31 $ 4 $ 5 Interest cost 217 52 76 10 10 Expected return on plan assets (323 ) (84 ) (113 ) (14 ) (14 ) Amortization: Prior service costs 13 3 5 1 1 Net (gain)/loss 55 16 20 2 2 Net cost $ 69 $ 11 $ 19 $ 3 $ 4 Postretirement Benefits Southern Company Alabama Power Georgia Power Gulf Power Mississippi Power (in millions) Three Months Ended June 30, 2015 Service cost $ 5 $ 2 $ 1 $ — $ 1 Interest cost 20 5 9 1 1 Expected return on plan assets (14 ) (7 ) (6 ) (1 ) (1 ) Amortization: Prior service costs 1 — — — — Net (gain)/loss 4 1 3 — — Net cost $ 16 $ 1 $ 7 $ — $ 1 Six Months Ended June 30, 2015 Service cost $ 11 $ 3 $ 3 $ — $ 1 Interest cost 39 10 17 2 2 Expected return on plan assets (29 ) (13 ) (12 ) (1 ) (1 ) Amortization: Prior service costs 2 1 — — — Net (gain)/loss 9 1 6 — — Net cost $ 32 $ 2 $ 14 $ 1 $ 2 Three Months Ended June 30, 2014 Service cost $ 6 $ 2 $ 1 $ 1 $ 1 Interest cost 20 5 9 1 1 Expected return on plan assets (15 ) (7 ) (7 ) (1 ) (1 ) Amortization: Prior service costs 1 1 — — — Net (gain)/loss — — 1 — — Net cost $ 12 $ 1 $ 4 $ 1 $ 1 Six Months Ended June 30, 2014 Service cost $ 11 $ 3 $ 3 $ 1 $ 1 Interest cost 40 10 17 2 2 Expected return on plan assets (30 ) (13 ) (13 ) (1 ) (1 ) Amortization: Prior service costs 2 2 — — — Net (gain)/loss 1 — 1 — — Net cost $ 24 $ 2 $ 8 $ 2 $ 2

Income Taxes (Tables)

Income Taxes (Tables)	6 Months Ended
	Jun. 30, 2015
Income Tax Disclosure [Abstract]
Change in Unrecognized Tax Benefits	Changes during 2015 for unrecognized tax benefits were as follows: Mississippi Power Southern Power Southern Company (in millions) Unrecognized tax benefits as of December 31, 2014 $ 165 $ 5 $ 170 Tax positions from current periods — 2 2 Tax positions from prior periods 230 — 231 Reductions due to settlements (5 ) — (5 ) Balance as of June 30, 2015 $ 390 $ 7 $ 398
Impact on Effective Tax Rate, If Recognized	The impact on the effective tax rate, if recognized, was as follows: As of June 30, 2015 As of December 31, 2014 Mississippi Power Southern Power Southern Company Southern Company (in millions) Tax positions impacting the effective tax rate $ — $ 7 $ 8 $ 10 Tax positions not impacting the effective tax rate 390 — 390 160 Balance of unrecognized tax benefits $ 390 $ 7 $ 398 $ 170

Derivatives (Tables)

Derivatives (Tables)	6 Months Ended
	Jun. 30, 2015
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of derivatives	At June 30, 2015 , the net volume of energy-related derivative contracts for natural gas positions for the Southern Company system, together with the longest hedge date over which the respective entity is hedging its exposure to the variability in future cash flows for forecasted transactions and the longest non-hedge date for derivatives not designated as hedges, were as follows: Net Purchased mmBtu Longest Hedge Date Longest Non-Hedge Date (in millions) Southern Company 220 2020 2017 Alabama Power 49 2018 — Georgia Power 47 2017 — Gulf Power 80 2020 — Mississippi Power 43 2018 — Southern Power 1 2015 2017
Notional amount of interest rate derivatives	At June 30, 2015 , the following interest rate derivatives were outstanding: Notional Amount Interest Rate Received Weighted Average Interest Rate Paid Hedge Maturity Date Fair Value 2015 (in millions) (in millions) Cash Flow Hedges of Forecasted Debt Alabama Power $ 200 3-month 2.93% October 2025 $ (7 ) Georgia Power 350 3-month 2.57% November 2025 (1 ) Cash Flow Hedges of Existing Debt Georgia Power 250 3-month 0.75% March 2016 — Georgia Power 200 3-month 1.01% August 2016 — Fair Value Hedges on Existing Debt Southern Company 250 1.30% 3-month August 2017 2 Southern Company 300 2.75% 3-month LIBOR + 0.92% June 2020 1 Georgia Power 250 5.40% 3-month June 2018 1 Georgia Power 200 4.25% 3-month December 2019 1 Total $ 2,000 $ (3 )
Fair value of energy-related derivatives and interest rate derivatives	At June 30, 2015 , the fair value of energy-related derivatives and interest rate derivatives was reflected in the balance sheets as follows: Asset Derivatives at June 30, 2015 Fair Value Derivative Category and Balance Sheet Location Southern Company Alabama Power Georgia Power Gulf Power Mississippi Power Southern Power (in millions) Derivatives designated as hedging instruments for regulatory purposes Energy-related derivatives: Other current assets $ 5 $ 2 $ 3 $ — $ — N/A Derivatives designated as hedging instruments in cash flow and fair value hedges Interest rate derivatives: Other current assets $ 11 $ — $ 5 $ — $ — $ — Total asset derivatives $ 16 $ 2 $ 8 $ — $ — $ — Liability Derivatives at June 30, 2015 Fair Value Derivative Category and Balance Sheet Location Southern Company Alabama Power Georgia Power Gulf Power Mississippi Power Southern Power (in millions) Derivatives designated as hedging instruments for regulatory purposes Energy-related derivatives: Other current liabilities (*) $ 99 $ 31 $ 15 $ 32 $ 21 Other deferred credits and liabilities 81 17 2 42 20 Total derivatives designated as hedging instruments for regulatory purposes $ 180 $ 48 $ 17 $ 74 $ 41 N/A Derivatives designated as hedging instruments in cash flow and fair value hedges Interest rate derivatives: Other current liabilities (*) $ 8 $ 7 $ 1 $ — $ — $ — Other deferred credits and liabilities 6 — 3 — — — Total derivatives designed as hedging instruments in cash flow and fair value hedges $ 14 $ 7 $ 4 $ — $ — $ — Total liability derivatives $ 194 $ 55 $ 21 $ 74 $ 41 $ — (*) Gulf Power includes current liabilities related to derivatives designated as hedging instruments in "Liabilities from risk management activities." At December 31, 2014 , the fair value of energy-related derivatives and interest rate derivatives was reflected in the balance sheets as follows: Asset Derivatives at December 31, 2014 Fair Value Derivative Category and Balance Sheet Location Southern Company Alabama Power Georgia Power Gulf Power Mississippi Power Southern Power (in millions) Derivatives designated as hedging instruments for regulatory purposes Energy-related derivatives: Other current assets $ 7 $ 1 $ 6 $ — $ — Other deferred charges and assets — — 1 — — Total derivatives designated as hedging instruments for regulatory purposes $ 7 $ 1 $ 7 $ — $ — N/A Derivatives designated as hedging instruments in cash flow and fair value hedges Interest rate derivatives: Other current assets $ 7 $ — $ 5 $ — $ — $ — Other deferred charges and assets 1 — 1 — — — Total derivatives designated as hedging instruments in cash flow and fair value hedges $ 8 $ — $ 6 $ — $ — $ — Derivatives not designated as hedging instruments Energy-related derivatives: Other current assets $ 6 $ — $ — $ — $ — $ 5 Total asset derivatives $ 21 $ 1 $ 13 $ — $ — $ 5 Liability Derivatives at December 31, 2014 Fair Value Derivative Category and Balance Sheet Location Southern Company Alabama Power Georgia Power Gulf Power Mississippi Power Southern Power (in millions) Derivatives designated as hedging instruments for regulatory purposes Energy-related derivatives: Other current liabilities (*) $ 118 $ 32 $ 23 $ 37 $ 26 Other deferred credits and liabilities 79 21 4 35 19 Total derivatives designated as hedging instruments for regulatory purposes $ 197 $ 53 $ 27 $ 72 $ 45 N/A Derivatives designated as hedging instruments in cash flow and fair value hedges Interest rate derivatives: Other current liabilities (*) $ 17 $ 8 $ 9 $ — $ — $ — Other deferred credits and liabilities 7 — 5 — — — Total derivatives designated as hedging instruments in cash flow and fair value hedges $ 24 $ 8 $ 14 $ — $ — $ — Derivatives not designated as hedging instruments Energy-related derivatives: Other current liabilities $ 4 $ — $ — $ — $ — $ 4 Total liability derivatives $ 225 $ 61 $ 41 $ 72 $ 45 $ 4 (*) Gulf Power includes current liabilities related to derivatives designated as hedging instruments in "Liabilities from risk management activities."
Offsetting disclosure tables	Amounts related to energy-related derivative contracts and interest rate derivative contracts at June 30, 2015 and December 31, 2014 are presented in the following tables. Derivative Contracts at June 30, 2015 Fair Value Southern Company Alabama Power Georgia Power Gulf Power Mississippi Power Southern Power (in millions) Assets Energy-related derivatives: Energy-related derivatives presented in the Balance Sheet (a) $ 5 $ 2 $ 3 $ — $ — $ — Gross amounts not offset in the Balance Sheet (b) (5 ) (2 ) (3 ) — — — Net energy-related derivative assets $ — $ — $ — $ — $ — $ — Interest rate derivatives: Interest rate derivatives presented in the Balance Sheet (a) $ 11 $ — $ 5 $ — $ — $ — Gross amounts not offset in the Balance Sheet (b) (8 ) — (3 ) — — — Net interest rate derivative assets $ 3 $ — $ 2 $ — $ — $ — Liabilities Energy-related derivatives: Energy-related derivatives presented in the Balance Sheet (a) $ 180 $ 48 $ 17 $ 74 $ 41 $ — Gross amounts not offset in the Balance Sheet (b) (5 ) (2 ) (3 ) — — — Net energy-related derivative liabilities $ 175 $ 46 $ 14 $ 74 $ 41 $ — Interest rate derivatives: Interest rate derivatives presented in the Balance Sheet (a) $ 14 $ 7 $ 4 $ — $ — $ — Gross amounts not offset in the Balance Sheet (b) (8 ) — (3 ) — — — Net interest rate derivative liabilities $ 6 $ 7 $ 1 $ — $ — $ — (a) None of the registrants offsets fair value amounts for multiple derivative instruments executed with the same counterparty on the balance sheets; therefore, gross and net amounts of derivative assets and liabilities presented on the balance sheets are the same. (b) Includes gross amounts subject to netting terms that are not offset on the balance sheets and any cash/financial collateral pledged or received. Derivative Contracts at December 31, 2014 Fair Value Southern Company Alabama Power Georgia Power Gulf Power Mississippi Power Southern Power (in millions) Assets Energy-related derivatives: Energy-related derivatives presented in the Balance Sheet (a) $ 13 $ 1 $ 7 $ — $ — $ 5 Gross amounts not offset in the Balance Sheet (b) (9 ) — (7 ) — — — Net energy-related derivative assets $ 4 $ 1 $ — $ — $ — $ 5 Interest rate derivatives: Interest rate derivatives presented in the Balance Sheet (a) $ 8 $ — $ 6 $ — $ — $ — Gross amounts not offset in the Balance Sheet (b) (8 ) — (6 ) — — — Net interest rate derivative assets $ — $ — $ — $ — $ — $ — Liabilities Energy-related derivatives: Energy-related derivatives presented in the Balance Sheet (a) $ 201 $ 53 $ 27 $ 72 $ 45 $ 4 Gross amounts not offset in the Balance Sheet (b) (9 ) — (7 ) — — — Net energy-related derivative liabilities $ 192 $ 53 $ 20 $ 72 $ 45 $ 4 Interest rate derivatives: Interest rate derivatives presented in the Balance Sheet (a) $ 24 $ 8 $ 14 $ — $ — $ — Gross amounts not offset in the Balance Sheet (b) (8 ) — (6 ) — — — Net interest rate derivative liabilities $ 16 $ 8 $ 8 $ — $ — $ — (a) None of the registrants offsets fair value amounts for multiple derivative instruments executed with the same counterparty on the balance sheets; therefore, gross and net amounts of derivative assets and liabilities presented on the balance sheets are the same. (b) Includes gross amounts subject to netting terms that are not offset on the balance sheets and any cash/financial collateral pledged or received.
Pre-tax effects of unrealized derivative gains (losses) arising from energy-related derivative instruments	At June 30, 2015 and December 31, 2014 , the pre-tax effects of unrealized derivative gains (losses) arising from energy-related derivative instruments designated as regulatory hedging instruments and deferred were as follows: Regulatory Hedge Unrealized Gain (Loss) Recognized on the Balance Sheet at June 30, 2015 Derivative Category and Balance Sheet Location Southern Company Alabama Power Georgia Power Gulf Power Mississippi Power (in millions) Energy-related derivatives: Other regulatory assets, current $ (99 ) $ (31 ) $ (15 ) $ (32 ) $ (21 ) Other regulatory assets, deferred (81 ) (17 ) (2 ) (42 ) (20 ) Other regulatory liabilities, current (a) 5 2 3 — — Other regulatory liabilities, deferred (b) — — — — — Total energy-related derivative gains (losses) $ (175 ) $ (46 ) $ (14 ) $ (74 ) $ (41 ) (a) Southern Company, Alabama Power, and Georgia Power include other regulatory liabilities, current in other current liabilities. (b) Georgia Power includes other regulatory liabilities, deferred in other deferred credits and liabilities. Regulatory Hedge Unrealized Gain (Loss) Recognized on the Balance Sheet at December 31, 2014 Derivative Category and Balance Sheet Location Southern Company Alabama Power Georgia Power Gulf Power Mississippi Power (in millions) Energy-related derivatives: Other regulatory assets, current $ (118 ) $ (32 ) $ (23 ) $ (37 ) $ (26 ) Other regulatory assets, deferred (79 ) (21 ) (4 ) (35 ) (19 ) Other regulatory liabilities, current (a) 7 1 6 — — Other regulatory liabilities, deferred (b) — — 1 — — Total energy-related derivative gains (losses) $ (190 ) $ (52 ) $ (20 ) $ (72 ) $ (45 ) (a) Southern Company, Alabama Power, and Georgia Power include other regulatory liabilities, current in other current liabilities. (b) Georgia Power includes other regulatory liabilities, deferred in other deferred credits and liabilities.
Pre-tax effects of interest rate derivatives	For the three months ended June 30, 2015 and 2014 , the pre-tax effects of interest rate derivatives designated as cash flow hedging instruments on the statements of income were as follows: Derivatives in Cash Flow Hedging Relationships Gain (Loss) Recognized in OCI on Derivative (Effective Portion) Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion) Statements of Income Location Amount 2015 2014 2015 2014 (in millions) (in millions) Southern Company Interest rate derivatives $ 31 $ — Interest expense, net of amounts capitalized $ (2 ) $ (2 ) Alabama Power Interest rate derivatives $ 7 $ — Interest expense, net of amounts capitalized $ (1 ) $ — Georgia Power Interest rate derivatives $ 24 $ — Interest expense, net of amounts capitalized $ (1 ) $ — Mississippi Power Interest rate derivatives $ — $ — Interest expense, net of amounts capitalized $ — $ (1 ) Southern Power Interest rate derivatives $ — $ — Interest expense, net of amounts capitalized $ — $ (1 )

Acquisitions (Tables)

Acquisitions (Tables)	6 Months Ended
	Jun. 30, 2015
Business Combinations [Abstract]
Schedule of Construction Projects	Southern Power Company's construction projects are detailed in the table below: Solar Project Seller Nameplate Capacity County Location in Georgia Expected Commercial Operation Date PPA Counterparty for Entire Plant Output PPA Contract Period Estimated Construction Cost (MW) (in millions) Taylor County N/A 146 Taylor Fourth quarter 2016 Cobb, Flint, and Sawnee Electric Membership Corporations 25 years $ 260 - $280 Decatur Parkway TradeWind Energy, Inc. 84 Decatur December 2015 Georgia Power (a) 25 years $ 170 - $173 (b) Decatur County TradeWind Energy, Inc. 20 Decatur December 2015 Georgia Power (a) 20 years $ 45 - $47 (b) Butler CERSM, LLC and Community Energy, Inc. 103 Taylor December 2016 Georgia Power (a) 30 years $ 220 - $230 (b) Pawpaw Longview Solar, LLC 30 Taylor December 2015 Georgia Power (a) 30 years $ 70 - $80 (b) Butler Solar Farm Strata Solar Development, LLC 20 Taylor December 2015 Georgia Power (a) 20 years $ 42 - $48 (b) (a) Subject to FERC approval. (b) Includes the acquisition price of all outstanding membership interests.

Segment and Related Informati29

Segment and Related Information (Tables)	6 Months Ended
	Jun. 30, 2015
Segment Reporting [Abstract]
Financial data for business segments	Financial data for business segments and products and services for the three and six months ended June 30, 2015 and 2014 was as follows: Electric Utilities Traditional Operating Companies Southern Power Eliminations Total All Other Eliminations Consolidated (in millions) Three Months Ended June 30, 2015: Operating revenues $ 4,077 $ 337 $ (90 ) $ 4,324 $ 43 $ (30 ) $ 4,337 Segment net income (loss) (a)(b) 561 46 — 607 18 4 629 Six Months Ended June 30, 2015: Operating revenues $ 8,025 $ 684 $ (213 ) $ 8,496 $ 83 $ (59 ) $ 8,520 Segment net income (loss) (a)(c) 1,038 79 — 1,117 21 — 1,138 Total assets at June 30, 2015 $ 67,362 $ 6,226 $ (277 ) $ 73,311 $ 1,360 $ (490 ) $ 74,181 Three Months Ended June 30, 2014: Operating revenues $ 4,209 $ 329 $ (84 ) $ 4,454 $ 39 $ (26 ) $ 4,467 Segment net income (loss) (a) 580 31 — 611 2 (2 ) 611 Six Months Ended June 30, 2014: Operating revenues $ 8,587 $ 680 $ (186 ) $ 9,081 $ 80 $ (50 ) $ 9,111 Segment net income (loss) (a)(c) 899 64 — 963 2 (3 ) 962 Total assets at December 31, 2014 $ 64,644 $ 5,550 $ (131 ) $ 70,063 $ 1,156 $ (296 ) $ 70,923 (a) After dividends on preferred and preference stock of subsidiaries. (b) Segment net income (loss) for the traditional operating companies for the three months ended June 30, 2015 includes a $23 million pre-tax charge ( $14 million after tax) for estimated probable losses on the Kemper IGCC. See Note (B) under "Integrated Coal Gasification Combined Cycle – Kemper IGCC Schedule and Cost Estimate" herein for additional information. (c) Segment net income (loss) for the traditional operating companies for the six months ended June 30, 2015 and June 30, 2014 includes a $32 million pre-tax charge ( $20 million after tax) and a $380 million pre-tax charge ( $235 million after tax), respectively, for estimated probable losses on the Kemper IGCC. See Note (B) under "Integrated Coal Gasification Combined Cycle – Kemper IGCC Schedule and Cost Estimate" herein for additional information.
Financial data for products and services	Products and Services Electric Utilities' Revenues Period Retail Wholesale Other Total (in millions) Three Months Ended June 30, 2015 $ 3,714 $ 448 $ 162 $ 4,324 Three Months Ended June 30, 2014 3,770 515 169 4,454 Six Months Ended June 30, 2015 $ 7,256 $ 915 $ 325 $ 8,496 Six Months Ended June 30, 2014 7,628 1,119 334 9,081

Introduction - Narrative (Detai

Introduction - Narrative (Details) $ in Millions		Aug. 05, 2015USD ($)	Feb. 06, 2015MW	Jun. 30, 2015USD ($)		Jun. 30, 2014USD ($)	Jun. 30, 2015USD ($)		Jun. 30, 2014USD ($)
Public Utility, Property, Plant and Equipment [Line Items]
Decrease to net income	[1]			$ (629)	[2]	$ (611)	$ (1,138)	[3]	$ (962)	[3]
Asset Retirement Obligation, Liabilities Incurred							612
Gulf Power [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Decrease in retail revenues				(327)		(310)	(620)		(613)
Decrease to net income				(35)		(34)	(72)		(71)
Asset Retirement Obligation, Liabilities Incurred							71
Georgia Power [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Decrease in retail revenues				(1,872)		(2,000)	(3,686)		(4,050)
Decrease to net income				(277)		(311)	(513)		(577)
Asset Retirement Obligation, Liabilities Incurred							0
Mississippi Power [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Decrease in retail revenues				(189)		(211)	(357)		(418)
Decrease to net income				(49)		$ (62)	(84)		$ 110
Asset Retirement Obligation, Liabilities Incurred							$ 97
Plant Smith Units 1 and 2 [Member] | Gulf Power [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Capacity Of Units Included In Request For Decertification Of Units (in MWs) | MW			357
Restatement Adjustment [Member] | Georgia Power [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Decrease in retail revenues				75
Decrease to net income				$ 47
Minimum [Member] | Scenario, Forecast [Member] | Gulf Power [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Asset Retirement Obligation, Liabilities Incurred		$ 15
Maximum [Member] | Scenario, Forecast [Member] | Gulf Power [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Asset Retirement Obligation, Liabilities Incurred		$ 35
[1]	After dividends on preferred and preference stock of subsidiaries.
[2]	Segment net income (loss) for the traditional operating companies for the three months ended June 30, 2015 includes a $23 million pre-tax charge ($14 million after tax) for estimated probable losses on the Kemper IGCC. See Note (B) under "Integrated Coal Gasification Combined Cycle – Kemper IGCC Schedule and Cost Estimate" herein for additional information.
[3]	Segment net income (loss) for the traditional operating companies for the six months ended June 30, 2015 and June 30, 2014 includes a $32 million pre-tax charge ($20 million after tax) and a $380 million pre-tax charge ($235 million after tax), respectively, for estimated probable losses on the Kemper IGCC. See Note (B) under "Integrated Coal Gasification Combined Cycle – Kemper IGCC Schedule and Cost Estimate" herein for additional information.

Introduction - Asset Retirement

Introduction - Asset Retirement Obligations (Details) $ in Millions	6 Months Ended
	Jun. 30, 2015USD ($)
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Balance at beginning of year	$ 2,201
Liabilities incurred	612
Liabilities settled	(10)
Accretion	53
Cash flow revisions	58
Balance at end of period	2,914
Alabama Power [Member]
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Balance at beginning of year	829
Liabilities incurred	401
Liabilities settled	(1)
Accretion	23
Cash flow revisions	0
Balance at end of period	1,252
Georgia Power [Member]
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Balance at beginning of year	1,255
Liabilities incurred	0
Liabilities settled	(9)
Accretion	28
Cash flow revisions	82
Balance at end of period	1,356
Gulf Power [Member]
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Balance at beginning of year	17
Liabilities incurred	71
Liabilities settled	0
Accretion	0
Cash flow revisions	4
Balance at end of period	92
Mississippi Power [Member]
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Balance at beginning of year	48
Liabilities incurred	97
Liabilities settled	0
Accretion	1
Cash flow revisions	2
Balance at end of period	$ 148

Contingencies and Regulatory 32

Contingencies and Regulatory Matters - Retail Regulatory Matters (Details) - Alabama Power [Member] - USD ($) $ in Millions		Jun. 30, 2015	Dec. 31, 2014
Deferred Under Recovered Regulatory Clause Revenues [Member]
Loss Contingencies [Line Items]
Under Recovered Rate Cnp Balance	[1]	$ 25	$ 2
Rate Cnp Power Purchase Agreement		72	29
Under Recovered Regulatory Clause Revenues [Member]
Loss Contingencies [Line Items]
Under Recovered Rate Cnp Balance, Current		29	47
Rate Cnp Power Purchase Agreement		0	27
Deferred Over Recovered Regulatory Clause Revenues [Member]
Loss Contingencies [Line Items]
Retail Energy Cost Recovery - Over		72	47
Other regulatory liabilities deferred [Member]
Loss Contingencies [Line Items]
Accumulated reserve balance for future storms		$ 81	$ 84
[1]	Formerly Known As Rate CNP Environmental

Contingencies and Regulatory 33

Contingencies and Regulatory Matters - Cost Recovery Clause (Details) - Under Recovered Regulatory Clause Revenues [Member] - Gulf Power [Member] - USD ($) $ in Millions	Jun. 30, 2015	Dec. 31, 2014
Loss Contingencies [Line Items]
Under Recovered Fuel Cost	$ 24	$ 40
Under Recovered Purchased Power Capacity Costs	2	0
Under Recovered Environmental Cost	7	10
Under Recovered Energy Conservation Costs	$ 0	$ 3

Contingencies and Regulatory 34

Contingencies and Regulatory Matters - Current And Actual Cost Estimate (Details) - Mississippi Power [Member] - USD ($) $ in Millions		Jun. 30, 2015	Apr. 01, 2015	Jun. 30, 2015		Dec. 31, 2012	May. 20, 2015	Dec. 31, 2014	Oct. 06, 2014
Loss Contingencies [Line Items]
Interest Bearing Refundable Deposit Related to Assets Sale		$ 0		$ 0			$ 275	$ 275
Increase (decrease) in AFUDC Cost			$ 11
Kemper Igcc [Member]
Loss Contingencies [Line Items]
Plant Subject to Cost Cap				4,510	[1]	$ 2,880
Lignite Mine and Equipment				230
CO2 Pipeline Facilities				110
Cost Of AFUDC	[2],[3]			520
Combined Cycle And Related Assets Placed In Service, Incremental	[4]			0
General Exceptions				80
Deferred Costs	[2],[5]			150
Maximum Cap Construction Cost	[1],[2]			5,600
Purchase of Interest									15.00%
Increase (decrease) in AFUDC Cost		$ (11)	$ 8
Project Estimate [Member] | Kemper Igcc [Member]
Loss Contingencies [Line Items]
Plant Subject to Cost Cap	[1],[6]			2,400
Lignite Mine and Equipment	[6]			210
CO2 Pipeline Facilities	[6]			140
Cost Of AFUDC	[2],[3],[6]			170
Combined Cycle And Related Assets Placed In Service, Incremental	[4],[6]			0
General Exceptions	[6]			50
Deferred Costs	[2],[5],[6]			0
Maximum Cap Construction Cost	[1],[2],[6]			2,970
Current Estimate [Member] | Kemper Igcc [Member]
Loss Contingencies [Line Items]
Plant Subject to Cost Cap	[1]			4,960
Lignite Mine and Equipment				230
CO2 Pipeline Facilities				110
Cost Of AFUDC	[2],[3]			620
Combined Cycle And Related Assets Placed In Service, Incremental	[4]			20
General Exceptions				100
Deferred Costs	[2],[5]			190
Maximum Cap Construction Cost	[1],[2]			$ 6,230
[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. The Current Estimate and Actual Costs include non-incremental operating and maintenance costs related to the combined cycle and associated common facilities placed in service in August 2014 that are subject to the $2.88 billion cost cap and exclude post-in-service costs for the lignite mine. See "Rate Recovery of Kemper IGCC Costs – 2013 MPSC Rate Order" for additional information. The Current Estimate and Actual Costs include the 15% undivided interest in the Kemper IGCC that was previously projected to be purchased by SMEPA. On May 20, 2015, SMEPA notified Mississippi Power of its termination of the asset purchase agreement (APA) and requested the return of a total of $275 million of deposits, which was returned with accrued interest on June 3, 2015.
[2]	Amounts in the Current Estimate reflect estimated costs through March 31, 2016.
[3]	Mississippi Power's original estimate included recovery of financing costs during construction rather than the accrual of AFUDC. This approach was not approved by the Mississippi PSC in 2012 as described in "Rate Recovery of Kemper IGCC Costs." The current estimate includes an approximately $11 million decrease in AFUDC due to a decrease in AFUDC rates resulting from an increase in short-term debt, partially offset by an $8 million increase in AFUDC related to a settlement agreement with the wholesale customers for cost-based rates under FERC's jurisdiction. See "FERC Matters" herein for additional information.
[4]	Incremental operating and maintenance costs related to the combined cycle and associated common facilities placed in service in August 2014, net of costs related to energy sales. See "Rate Recovery of Kemper IGCC Costs – 2013 MPSC Rate Order" for additional information.
[5]	The 2012 MPSC CPCN Order approved deferral of non-capital Kemper IGCC-related costs during construction as described in "Rate Recovery of Kemper IGCC Costs – Regulatory Assets and Liabilities."
[6]	The 2010 Project Estimate is the certificated cost estimate adjusted to include the certificated estimate for the CO2 pipeline facilities which was approved in 2011 by the Mississippi PSC.

Contingencies and Regulatory 35

Contingencies and Regulatory Matters - Narrative (Details)		Aug. 05, 2015MW	Jul. 10, 2015USD ($)	Jun. 30, 2015USD ($)mi	Jun. 25, 2015USD ($)	Jun. 03, 2015USD ($)	May. 15, 2015USD ($)	Apr. 16, 2015USD ($)MW	Apr. 01, 2015USD ($)	Mar. 10, 2015USD ($)	Feb. 27, 2015USD ($)	Feb. 25, 2015USD ($)	Jan. 29, 2015	Jan. 01, 2014USD ($)	Mar. 19, 2013	Jun. 30, 2015USD ($)mi	May. 31, 2015USD ($)	Apr. 30, 2015MW	Dec. 31, 2014USD ($)	Dec. 31, 2013USD ($)	Feb. 28, 2013USD ($)	Jan. 31, 2013USD ($)	Jun. 30, 2015USD ($)mi	Mar. 31, 2015USD ($)	Jun. 30, 2014USD ($)	Jun. 30, 2015USD ($)clausemiMW		Dec. 31, 2014USD ($)	Jun. 30, 2014USD ($)	Dec. 31, 2014USD ($)	Dec. 31, 2013USD ($)	Dec. 31, 2012USD ($)	Dec. 31, 2010	Dec. 31, 2008USD ($)	Jun. 30, 2014USD ($)	Jun. 30, 2015USD ($)mi	May. 20, 2015USD ($)	Apr. 23, 2015USD ($)	Feb. 02, 2015USD ($)	Oct. 06, 2014
Loss Contingencies [Line Items]
Revenues																							$ 4,337,000,000		$ 4,467,000,000	$ 8,520,000,000			$ 9,111,000,000
Asset Retirement Obligation				$ 2,914,000,000												$ 2,914,000,000			$ 2,201,000,000				2,914,000,000			2,914,000,000		$ 2,201,000,000		$ 2,201,000,000						$ 2,914,000,000
Return Of Interest Bearing Refundable Deposits Related to Assets Sale Plus Accrued Interest						$ 301,000,000
Unrecognized Tax Benefits				398,000,000												398,000,000			170,000,000				398,000,000			398,000,000		170,000,000		170,000,000						398,000,000
Kemper IGCC [Member]
Loss Contingencies [Line Items]
Pre-tax charge to income																							23,000,000			32,000,000			380,000,000	868,000,000	$ 1,200,000,000
After tax charge to income																							14,000,000			20,000,000			235,000,000	536,000,000	729,000,000
Unrecognized Tax Benefits				390,000,000												390,000,000							390,000,000			390,000,000										390,000,000
Alabama Power [Member]
Loss Contingencies [Line Items]
Civil Penalties Payment Related to NSR					$ 100,000
Civil Penalties Required Investment In Electric Transportation Infrastructure Projects					$ 1,500,000
Period to Invest in Electric Transportation Infrastructure Projects					3 years
Claims Awarded to Companies Related to Nuclear Fuel Disposal Litigation																			26,000,000
Non-environmental Costs																										30,000,000
Recovery Of Non-environmental Costs																										50,000,000
Electric Generating Units, Capacity (in MW's) | MW																		12,200
Revenues																							1,455,000,000		1,437,000,000	2,856,000,000			2,945,000,000
Asset Retirement Obligation				1,252,000,000												1,252,000,000			829,000,000				1,252,000,000			1,252,000,000		829,000,000		829,000,000						1,252,000,000
Alabama Power [Member] | Plant Gorgas Units 6 and 7 [Member]
Loss Contingencies [Line Items]
Capacity Of Units Included In Request For Decertification Of Units (in MWs) | MW																		200
Alabama Power [Member] | Plant Barry Units 1 And 2 [Member]
Loss Contingencies [Line Items]
Capacity Of Units Included In Request For Decertification Of Units (in MWs) | MW																		250
Georgia Power [Member]
Loss Contingencies [Line Items]
Environmental Exit Costs, Assets Previously Disposed, Liability for Remediation				40,000,000												40,000,000							40,000,000			40,000,000										40,000,000
Civil penalties per day violation rate				$ 37,500												$ 37,500							$ 37,500			$ 37,500										$ 37,500
Number of times of punitive damages in comparison to cost incurred by Environmental Protection Agency				3												3							3			3										3
Claims Awarded to Companies Related to Nuclear Fuel Disposal Litigation																			18,000,000
Additional Construction Capital Costs																												200,000,000							$ 2,800,000,000
Percentage of Proportionate Share Owed in Consortium Agreement																																		45.70%
Increase (Decrease) In Projected Certified Construction Capital Costs																										5.00%
Delay Of Estimated In-service Date											18 months		18 months
Revenues																							$ 2,016,000,000		2,186,000,000	$ 3,994,000,000			4,455,000,000
Asset Retirement Obligation				$ 1,356,000,000												$ 1,356,000,000			1,255,000,000				1,356,000,000			1,356,000,000		1,255,000,000		1,255,000,000						$ 1,356,000,000
Georgia Power [Member] | Minimum [Member]
Loss Contingencies [Line Items]
Estimated In-service Capital Cost																										4,400,000,000					4,400,000,000
Georgia Power [Member] | Maximum [Member]
Loss Contingencies [Line Items]
Additional Construction Capital Costs																																		$ 114,000,000
Estimated In-service Capital Cost																															4,800,000,000
Georgia Power [Member] | Other deferred charges and assets [Member]
Loss Contingencies [Line Items]
Fuel cost recovery balance				106,000,000												106,000,000			199,000,000				106,000,000			106,000,000		199,000,000		199,000,000						106,000,000
Georgia Power [Member] | Plant Branch Units 1 and 3 and 4 [Member]
Loss Contingencies [Line Items]
Capacity Of Units Included In Request For Decertification Of Units (in MWs) | MW								1,266
Georgia Power [Member] | Plant Yates Units 1 through 5 [Member]
Loss Contingencies [Line Items]
Capacity Of Units Included In Request For Decertification Of Units (in MWs) | MW								579
Georgia Power [Member] | Plant McManus Units 1 and 2 [Member]
Loss Contingencies [Line Items]
Capacity Of Units Included In Request For Decertification Of Units (in MWs) | MW								122
Georgia Power [Member] | Plant Mitchell Unit 3 [Member]
Loss Contingencies [Line Items]
Electric Generating Units, Capacity (in MW's) | MW								155
Georgia Power [Member] | Plant Vogtle Units 3 And 4 [Member]
Loss Contingencies [Line Items]
Estimated In-service Capital Cost											$ 5,000,000,000
Monthly Operational Readiness Costs											$ 10,000,000
Monthly Financing Costs																										30,000,000
Construction Financing Costs																										2,500,000,000
Gulf Power [Member]
Loss Contingencies [Line Items]
Environmental Exit Costs, Assets Previously Disposed, Liability for Remediation				47,000,000												47,000,000							47,000,000			47,000,000										47,000,000
Reduction In Depreciation Expense																				$ 62,500,000
Reduction In Depreciation Expense Year One																										$ 19,600,000
Number Of Regulatory Clauses | clause																										4
Ownership percentage in scrubber project																																50.00%
Revenues																							384,000,000		384,000,000	$ 741,000,000			791,000,000
Asset Retirement Obligation				92,000,000												92,000,000			17,000,000				92,000,000			92,000,000		17,000,000		17,000,000						92,000,000
Mississippi Power [Member]
Loss Contingencies [Line Items]
Environmental Exit Costs, Assets Previously Disposed, Liability for Remediation				300,000												300,000							300,000			300,000										300,000
AFUDC Cost									$ 11,000,000
Psc Approved Annual Property Damage Reserve Accrual																																							$ 3,000,000
Ownership percentage in scrubber project																																50.00%
Estimated cost of scrubber project																																$ 330,000,000
Scrubber project expenditures amount				308,000,000												308,000,000							308,000,000			308,000,000										308,000,000
Allowance For Funds Used During Construction Cost																										27,000,000
Revenues												$ 8,000,000											275,000,000		$ 311,000,000	552,000,000			642,000,000
Over Recovered Fuel Cost				$ 24,000,000												$ 24,000,000							$ 24,000,000			$ 24,000,000										$ 24,000,000
Under recovered regulatory clause revenues																			2,000,000									2,000,000		2,000,000
Percentage Of PSC Retail Rate Increase (Decrease)																																						(0.35%)
PSC Retail Rate Increase (Decrease)																																						$ (2,000,000)
Plant Capacity Under Coal Gasification Combined Cycle Technology (in MWs) | MW																										582
Co Two Pipeline Infrastructure (in miles) | mi				61												61							61			61										61
Costs associated with CCP12 grant funds																																$ 245,000,000
Other Property And Investments				$ 2,000,000												$ 2,000,000							$ 2,000,000			$ 2,000,000										$ 2,000,000
Lignite Mining Costs				58,000,000												58,000,000							58,000,000			58,000,000										58,000,000
Materials, Supplies, and Other				41,000,000												41,000,000							41,000,000			41,000,000										41,000,000
Cost deferred in other regulatory assets				198,000,000												198,000,000							198,000,000			198,000,000										198,000,000
Other deferred charges and assets				16,000,000												16,000,000							16,000,000			16,000,000										16,000,000
Asset Retirement Obligation				148,000,000												148,000,000			48,000,000				148,000,000			148,000,000		48,000,000		48,000,000						148,000,000
Previously expensed				$ 1,000,000												$ 1,000,000							$ 1,000,000			$ 1,000,000										1,000,000
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
Retail Rate Recovery																																				331,000,000
Carrying Costs Associated With Retail Rate Recovery																																				$ 22,000,000
Percentage of Carbon Dioxide Captured from Project				70.00%												70.00%							70.00%			70.00%										70.00%
Percentage of Contract to Purchase Carbon Dioxide from Project				30.00%												30.00%							30.00%			30.00%										30.00%
Reduced percentage interest transferred under asset purchase agreement																																15.00%
Interest Bearing Refundable Deposit Related to Assets Sale				$ 0												$ 0			275,000,000				$ 0			$ 0		275,000,000		275,000,000						$ 0	$ 275,000,000
Issuance Of Promissory Note From Parent In Exchange For Repayment Of Interest-bearing Refundable Deposit And Accrued Interest						$ 301,000,000										$ 301,000,000										301,000,000			$ 0
Bank Loans Period Of Extension						18 months										18 months
Internal Revenue Code Section Forty Eight Tax Credits Phase I I																										279,000,000
Tax Credit Carryforward, Amount				276,000,000												$ 276,000,000							276,000,000			276,000,000										276,000,000
Tax Credit Carryforward Utilized				242,000,000												242,000,000							242,000,000			$ 242,000,000										242,000,000
Minimum percentage of carbon dioxide that must be capture and sequester to remain eligible for the phase II tax credits																										65.00%
Unrecognized Tax Benefits				390,000,000												390,000,000			$ 165,000,000				390,000,000			$ 390,000,000		$ 165,000,000		165,000,000						390,000,000
Mississippi Power [Member] | Minimum [Member]
Loss Contingencies [Line Items]
Costs Due To Extension Of In-service Date																										25,000,000
Mississippi Power [Member] | Maximum [Member]
Loss Contingencies [Line Items]
Costs Due To Extension Of In-service Date																										30,000,000
Mississippi Power [Member] | Construction in Progress [Member]
Loss Contingencies [Line Items]
Loss Contingency, Estimate of Possible Loss				2,080,000,000												2,080,000,000							2,080,000,000			2,080,000,000										2,080,000,000
Mississippi Power [Member] | Plant Watson Units 4 And 5 [Member]
Loss Contingencies [Line Items]
Net Book Value Of Units Included In Request For Decertification Of Units								$ 32,000,000
Mississippi Power [Member] | Kemper IGCC [Member]
Loss Contingencies [Line Items]
AFUDC Cost				(11,000,000)					$ 8,000,000
Estimated Cost																										4,510,000,000	[1]					$ 2,880,000,000
Asset Retirement Obligation				24,000,000												24,000,000							24,000,000			24,000,000										24,000,000
Pre-tax charge to income																							23,000,000	$ 9,000,000						868,000,000	1,100,000,000	78,000,000
After tax charge to income																							14,000,000	$ 6,000,000						536,000,000	$ 681,000,000	48,000,000
Monthly Charge Of Allowance For Equity Funds Used During Construction																										13,000,000
Monthly Cost Regulatory Assets Deferred																										7,000,000
Purchase of Interest																																								15.00%
Maximum Cap Construction Cost	[1],[2]																									5,600,000,000
Regulatory Assets				198,000,000												198,000,000							198,000,000			198,000,000										198,000,000
Projected Balance Of Regulatory Assets				276,000,000												276,000,000							276,000,000			276,000,000										276,000,000
Unrecognized Tax Benefits				390,000,000												390,000,000							390,000,000			390,000,000										390,000,000
Mississippi Power [Member] | Kemper IGCC [Member] | Current Estimate [Member]
Loss Contingencies [Line Items]
Estimated Cost	[1]																									4,960,000,000
Maximum Cap Construction Cost	[1],[2]																									6,230,000,000
Mississippi Power [Member] | Kemper IGCC [Member] | Traditional Rate Case [Member]
Loss Contingencies [Line Items]
Increase Retail Rates In Year One							11.80%
Increase Retail Rates In Year Two							12.00%
PSC Retail Rate Increase (Decrease) in Year One							$ 114,000,000
PSC Retail Rate Increase (Decrease) in Year Two							$ 120,000,000
Mississippi Power [Member] | Kemper IGCC [Member] | Rate Mitigation Plan 2017 [Member]
Loss Contingencies [Line Items]
Increase Retail Rates In Year One							2.60%
Increase Retail Rates In Year Two							19.00%
PSC Retail Rate Increase (Decrease) in Year One							$ 25,000,000
PSC Retail Rate Increase (Decrease) in Year Two							$ 197,000,000
Mississippi Power [Member] | Kemper IGCC [Member] | Property, Plant and Equipment [Member]
Loss Contingencies [Line Items]
Estimated Cost																										3,420,000,000
Mississippi Power [Member] | Electricity Generation Plant, Non-Nuclear [Member]
Loss Contingencies [Line Items]
Estimated Cost																						$ 2,400,000,000
Alternate Financing																					$ 1,000,000,000
Mississippi Power [Member] | Mine [Member]
Loss Contingencies [Line Items]
Term of Management Fee Contract																																	40 years
Gulf Power and Mississippi Power [Member]
Loss Contingencies [Line Items]
Estimated cost of scrubber project																																$ 660,000,000
Scrubber project expenditures amount				$ 604,000,000												604,000,000							$ 604,000,000			$ 604,000,000										$ 604,000,000
Subsequent Event [Member] | Alabama Power [Member] | Plant Greene County Units 1 And 2 [Member]
Loss Contingencies [Line Items]
Capacity Of Units Included In Request For Decertification Of Units (in MWs) | MW		300
Subsequent Event [Member] | Alabama Power [Member] | Plant Barry Unit 3 [Member]
Loss Contingencies [Line Items]
Capacity Of Units Included In Request For Decertification Of Units (in MWs) | MW		225
Subsequent Event [Member] | Mississippi Power [Member] | Kemper IGCC [Member]
Loss Contingencies [Line Items]
Period Of Inaction By The Public Service Commission For Rate Case Review			120 days
Subsequent Event [Member] | Mississippi Power [Member] | Kemper IGCC [Member] | In-Service Asset Proposal [Member]
Loss Contingencies [Line Items]
PSC Retail Rate Increase (Decrease)			$ 159,000,000
Pending Litigation [Member] | Plant Vogtle Units 3 And 4 [Member] | Georgia Power [Member] | Minimum [Member]
Loss Contingencies [Line Items]
Reduction in Projected in Service Cost due to Recovered Cost										$ 591,000,000																								$ 425,000,000
Damages In Connection With Counterclaim																$ 714,000,000	$ 118,000,000													$ 113,000,000
[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. The Current Estimate and Actual Costs include non-incremental operating and maintenance costs related to the combined cycle and associated common facilities placed in service in August 2014 that are subject to the $2.88 billion cost cap and exclude post-in-service costs for the lignite mine. See "Rate Recovery of Kemper IGCC Costs – 2013 MPSC Rate Order" for additional information. The Current Estimate and Actual Costs include the 15% undivided interest in the Kemper IGCC that was previously projected to be purchased by SMEPA. On May 20, 2015, SMEPA notified Mississippi Power of its termination of the asset purchase agreement (APA) and requested the return of a total of $275 million of deposits, which was returned with accrued interest on June 3, 2015.
[2]	Amounts in the Current Estimate reflect estimated costs through March 31, 2016.

Fair Value Measurements - Asset

Fair Value Measurements - Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Millions		Jun. 30, 2015	Dec. 31, 2014
Fair Value, Measurements, Recurring [Member]
Assets:
Energy-related derivatives		$ 5
Interest rate derivatives		11
Nuclear decommissioning trusts	[1]	1,571
Cash equivalents		533
Other investments		10
Total		2,130
Liabilities:
Energy-related derivatives		180
Interest rate derivatives		14
Total		194
Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Assets:
Energy-related derivatives		0
Interest rate derivatives		0
Nuclear decommissioning trusts	[1]	677
Cash equivalents		533
Other investments		9
Total		1,219
Liabilities:
Energy-related derivatives		0
Interest rate derivatives		0
Total		0
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member]
Assets:
Energy-related derivatives		5
Interest rate derivatives		11
Nuclear decommissioning trusts	[1]	887
Cash equivalents		0
Other investments		0
Total		903
Liabilities:
Energy-related derivatives		180
Interest rate derivatives		14
Total		194
Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member]
Assets:
Energy-related derivatives		0
Interest rate derivatives		0
Nuclear decommissioning trusts	[1]	7
Cash equivalents		0
Other investments		1
Total		8
Liabilities:
Energy-related derivatives		0
Interest rate derivatives		0
Total		0
Alabama Power [Member]
Assets:
Energy-related derivatives		2	$ 1
Liabilities:
Energy-related derivatives		55	61
Alabama Power [Member] | Fair Value, Measurements, Recurring [Member]
Assets:
Energy-related derivatives		2
Cash equivalents		81
Total		840
Liabilities:
Energy-related derivatives		48
Interest rate derivatives		7
Total		55
Alabama Power [Member] | Fair Value, Measurements, Recurring [Member] | Domestic Equity [Member]
Assets:
Nuclear decommissioning trusts	[2]	459
Alabama Power [Member] | Fair Value, Measurements, Recurring [Member] | Foreign equity [Member]
Assets:
Nuclear decommissioning trusts	[2]	101
Alabama Power [Member] | Fair Value, Measurements, Recurring [Member] | U.S. Treasury and government agency securities [Member]
Assets:
Nuclear decommissioning trusts	[2]	36
Alabama Power [Member] | Fair Value, Measurements, Recurring [Member] | Corporate bonds [Member]
Assets:
Nuclear decommissioning trusts	[2]	131
Alabama Power [Member] | Fair Value, Measurements, Recurring [Member] | Mortgage and asset backed securities [Member]
Assets:
Nuclear decommissioning trusts	[2]	17
Alabama Power [Member] | Fair Value, Measurements, Recurring [Member] | Other investments [Member]
Assets:
Nuclear decommissioning trusts	[2]	13
Alabama Power [Member] | Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Assets:
Energy-related derivatives		0
Cash equivalents		81
Total		523
Liabilities:
Energy-related derivatives		0
Interest rate derivatives		0
Total		0
Alabama Power [Member] | Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Domestic Equity [Member]
Assets:
Nuclear decommissioning trusts	[2]	381
Alabama Power [Member] | Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Foreign equity [Member]
Assets:
Nuclear decommissioning trusts	[2]	51
Alabama Power [Member] | Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | U.S. Treasury and government agency securities [Member]
Assets:
Nuclear decommissioning trusts	[2]	0
Alabama Power [Member] | Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Corporate bonds [Member]
Assets:
Nuclear decommissioning trusts	[2]	10
Alabama Power [Member] | Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Mortgage and asset backed securities [Member]
Assets:
Nuclear decommissioning trusts	[2]	0
Alabama Power [Member] | Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Other investments [Member]
Assets:
Nuclear decommissioning trusts	[2]	0
Alabama Power [Member] | Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member]
Assets:
Energy-related derivatives		2
Cash equivalents		0
Total		310
Liabilities:
Energy-related derivatives		48
Interest rate derivatives		7
Total		55
Alabama Power [Member] | Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Domestic Equity [Member]
Assets:
Nuclear decommissioning trusts	[2]	78
Alabama Power [Member] | Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Foreign equity [Member]
Assets:
Nuclear decommissioning trusts	[2]	50
Alabama Power [Member] | Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | U.S. Treasury and government agency securities [Member]
Assets:
Nuclear decommissioning trusts	[2]	36
Alabama Power [Member] | Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Corporate bonds [Member]
Assets:
Nuclear decommissioning trusts	[2]	121
Alabama Power [Member] | Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Mortgage and asset backed securities [Member]
Assets:
Nuclear decommissioning trusts	[2]	17
Alabama Power [Member] | Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Other investments [Member]
Assets:
Nuclear decommissioning trusts	[2]	6
Alabama Power [Member] | Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member]
Assets:
Energy-related derivatives		0
Cash equivalents		0
Total		7
Liabilities:
Energy-related derivatives		0
Interest rate derivatives		0
Total		0
Alabama Power [Member] | Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Domestic Equity [Member]
Assets:
Nuclear decommissioning trusts	[2]	0
Alabama Power [Member] | Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Foreign equity [Member]
Assets:
Nuclear decommissioning trusts	[2]	0
Alabama Power [Member] | Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | U.S. Treasury and government agency securities [Member]
Assets:
Nuclear decommissioning trusts	[2]	0
Alabama Power [Member] | Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Corporate bonds [Member]
Assets:
Nuclear decommissioning trusts	[2]	0
Alabama Power [Member] | Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Mortgage and asset backed securities [Member]
Assets:
Nuclear decommissioning trusts	[2]	0
Alabama Power [Member] | Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Other investments [Member]
Assets:
Nuclear decommissioning trusts	[2]	7
Georgia Power [Member]
Assets:
Energy-related derivatives		8	13
Nuclear decommissioning trusts		39
Liabilities:
Energy-related derivatives		21	41
Georgia Power [Member] | Fair Value, Measurements, Recurring [Member]
Assets:
Energy-related derivatives		3
Interest rate derivatives		5
Total		822
Liabilities:
Energy-related derivatives		17
Interest rate derivatives		4
Total		21
Georgia Power [Member] | Fair Value, Measurements, Recurring [Member] | Domestic Equity [Member]
Assets:
Nuclear decommissioning trusts	[2],[3]	183
Georgia Power [Member] | Fair Value, Measurements, Recurring [Member] | Foreign equity [Member]
Assets:
Nuclear decommissioning trusts	[2],[3]	125
Georgia Power [Member] | Fair Value, Measurements, Recurring [Member] | U.S. Treasury and government agency securities [Member]
Assets:
Nuclear decommissioning trusts	[2],[3]	95
Georgia Power [Member] | Fair Value, Measurements, Recurring [Member] | Municipal bonds [Member]
Assets:
Nuclear decommissioning trusts	[2],[3]	78
Georgia Power [Member] | Fair Value, Measurements, Recurring [Member] | Corporate bonds [Member]
Assets:
Nuclear decommissioning trusts	[2],[3]	169
Georgia Power [Member] | Fair Value, Measurements, Recurring [Member] | Mortgage and asset backed securities [Member]
Assets:
Nuclear decommissioning trusts	[2],[3]	108
Georgia Power [Member] | Fair Value, Measurements, Recurring [Member] | Other investments [Member]
Assets:
Nuclear decommissioning trusts	[2],[3]	56
Georgia Power [Member] | Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Assets:
Energy-related derivatives		0
Interest rate derivatives		0
Total		235
Liabilities:
Energy-related derivatives		0
Interest rate derivatives		0
Total		0
Georgia Power [Member] | Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Domestic Equity [Member]
Assets:
Nuclear decommissioning trusts	[2],[3]	182
Georgia Power [Member] | Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Foreign equity [Member]
Assets:
Nuclear decommissioning trusts	[2],[3]	0
Georgia Power [Member] | Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | U.S. Treasury and government agency securities [Member]
Assets:
Nuclear decommissioning trusts	[2],[3]	0
Georgia Power [Member] | Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Municipal bonds [Member]
Assets:
Nuclear decommissioning trusts	[2],[3]	0
Georgia Power [Member] | Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Corporate bonds [Member]
Assets:
Nuclear decommissioning trusts	[2],[3]	0
Georgia Power [Member] | Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Mortgage and asset backed securities [Member]
Assets:
Nuclear decommissioning trusts	[2],[3]	0
Georgia Power [Member] | Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Other investments [Member]
Assets:
Nuclear decommissioning trusts	[2],[3]	53
Georgia Power [Member] | Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member]
Assets:
Energy-related derivatives		3
Interest rate derivatives		5
Total		587
Liabilities:
Energy-related derivatives		17
Interest rate derivatives		4
Total		21
Georgia Power [Member] | Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Domestic Equity [Member]
Assets:
Nuclear decommissioning trusts	[2],[3]	1
Georgia Power [Member] | Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Foreign equity [Member]
Assets:
Nuclear decommissioning trusts	[2],[3]	125
Georgia Power [Member] | Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | U.S. Treasury and government agency securities [Member]
Assets:
Nuclear decommissioning trusts	[2],[3]	95
Georgia Power [Member] | Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Municipal bonds [Member]
Assets:
Nuclear decommissioning trusts	[2],[3]	78
Georgia Power [Member] | Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Corporate bonds [Member]
Assets:
Nuclear decommissioning trusts	[2],[3]	169
Georgia Power [Member] | Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Mortgage and asset backed securities [Member]
Assets:
Nuclear decommissioning trusts	[2],[3]	108
Georgia Power [Member] | Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Other investments [Member]
Assets:
Nuclear decommissioning trusts	[2],[3]	3
Georgia Power [Member] | Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member]
Assets:
Energy-related derivatives		0
Interest rate derivatives		0
Total		0
Liabilities:
Energy-related derivatives		0
Interest rate derivatives		0
Total		0
Georgia Power [Member] | Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Domestic Equity [Member]
Assets:
Nuclear decommissioning trusts	[2],[3]	0
Georgia Power [Member] | Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Foreign equity [Member]
Assets:
Nuclear decommissioning trusts	[2],[3]	0
Georgia Power [Member] | Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | U.S. Treasury and government agency securities [Member]
Assets:
Nuclear decommissioning trusts	[2],[3]	0
Georgia Power [Member] | Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Municipal bonds [Member]
Assets:
Nuclear decommissioning trusts	[2],[3]	0
Georgia Power [Member] | Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Corporate bonds [Member]
Assets:
Nuclear decommissioning trusts	[2],[3]	0
Georgia Power [Member] | Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Mortgage and asset backed securities [Member]
Assets:
Nuclear decommissioning trusts	[2],[3]	0
Georgia Power [Member] | Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Other investments [Member]
Assets:
Nuclear decommissioning trusts	[2],[3]	0
Gulf Power [Member]
Assets:
Energy-related derivatives		0	0
Liabilities:
Energy-related derivatives		74	72
Gulf Power [Member] | Fair Value, Measurements, Recurring [Member]
Assets:
Cash equivalents		18
Liabilities:
Energy-related derivatives		74
Gulf Power [Member] | Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Assets:
Cash equivalents		18
Liabilities:
Energy-related derivatives		0
Gulf Power [Member] | Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member]
Assets:
Cash equivalents		0
Liabilities:
Energy-related derivatives		74
Gulf Power [Member] | Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member]
Assets:
Cash equivalents		0
Liabilities:
Energy-related derivatives		0
Mississippi Power [Member]
Assets:
Energy-related derivatives		0	0
Liabilities:
Energy-related derivatives		41	45
Mississippi Power [Member] | Fair Value, Measurements, Recurring [Member]
Assets:
Cash equivalents		182
Liabilities:
Energy-related derivatives		41
Mississippi Power [Member] | Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Assets:
Cash equivalents		182
Liabilities:
Energy-related derivatives		0
Mississippi Power [Member] | Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member]
Assets:
Cash equivalents		0
Liabilities:
Energy-related derivatives		41
Mississippi Power [Member] | Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member]
Assets:
Cash equivalents		0
Liabilities:
Energy-related derivatives		0
Southern Power [Member]
Assets:
Energy-related derivatives		0	5
Liabilities:
Energy-related derivatives		0	$ 4
Southern Power [Member] | Fair Value, Measurements, Recurring [Member]
Assets:
Cash equivalents		206
Southern Power [Member] | Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Assets:
Cash equivalents		206
Southern Power [Member] | Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member]
Assets:
Cash equivalents		0
Southern Power [Member] | Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member]
Assets:
Cash equivalents		$ 0
[1]	For additional detail, see the nuclear decommissioning trusts sections for Alabama Power and Georgia Power in this table.
[2]	Excludes receivables related to investment income, pending investment sales, payables related to pending investment purchases, and currencies.
[3]	Includes the investment securities pledged to creditors and collateral received and excludes payables related to the securities lending program. As of June 30, 2015, approximately $39 million of the fair market value of Georgia Power's nuclear decommissioning trust funds' securities were on loan to creditors under the funds' managers' securities lending program.

Fair Value Measurements - Fair

Fair Value Measurements - Fair Value Measurements Calculated at Net Asset Value Per Share (Details) - Jun. 30, 2015 - USD ($)	Total
Foreign equity 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	$ 125,000,000
Unfunded Commitments	$ 0
Redemption Frequency	Monthly
Redemption Notice Period	5 days
Redemption Notice Period, Description
Equity - 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	$ 50,000,000
Unfunded Commitments	$ 0
Redemption Frequency	Daily
Redemption Notice Period, Description
Debt - 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	$ 16,000,000
Unfunded Commitments	$ 0
Redemption Frequency	Daily
Redemption Notice Period	5 days
Redemption Notice Period, Description
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	$ 3,000,000
Unfunded Commitments	$ 0
Redemption Frequency	Daily
Redemption Notice Period, Description
Other - 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	$ 53,000,000
Unfunded Commitments	$ 0
Redemption Frequency	Daily
Redemption Notice Period, Description
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	$ 117,000,000
Unfunded Commitments	$ 0
Redemption Frequency	Daily
Redemption Notice Period	15 days
Redemption Notice Period, Description
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	$ 533,000,000
Unfunded Commitments	$ 0
Redemption Frequency	Daily
Redemption Notice Period, Description
Alabama Power [Member] | Equity - 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	$ 50,000,000
Unfunded Commitments	$ 0
Redemption Frequency	Daily
Redemption Notice Period, Description
Alabama Power [Member] | Debt - 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	$ 16,000,000
Unfunded Commitments	$ 0
Redemption Frequency	Daily
Redemption Notice Period	5 days
Redemption Notice Period, Description
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	$ 117,000,000
Unfunded Commitments	$ 0
Redemption Frequency	Daily
Redemption Notice Period	15 days
Redemption Notice Period, Description
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	$ 81,000,000
Unfunded Commitments	$ 0
Redemption Frequency	Daily
Redemption Notice Period, Description
Georgia Power [Member] | Foreign equity 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	$ 125,000,000
Unfunded Commitments	$ 0
Redemption Frequency	Monthly
Redemption Notice Period	5 days
Redemption Notice Period, Description
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	$ 3,000,000
Unfunded Commitments	$ 0
Redemption Frequency	Daily
Redemption Notice Period, Description
Georgia Power [Member] | Other - 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	$ 53,000,000
Unfunded Commitments	$ 0
Redemption Frequency	Daily
Redemption Notice Period, Description
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	$ 18,000,000
Unfunded Commitments	$ 0
Redemption Frequency	Daily
Redemption Notice Period, Description
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	$ 182,000,000
Unfunded Commitments	$ 0
Redemption Frequency	Daily
Redemption Notice Period, Description
Southern 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	$ 206,000,000
Unfunded Commitments	$ 0
Redemption Frequency	Daily
Redemption Notice Period, Description

Fair Value Measurements - Finan

Fair Value Measurements - Financial Instruments for which Carrying Amount did not Equal Fair Value (Details) $ in Millions	Jun. 30, 2015USD ($)
Southern Company [Member]
Long-term debt:
Long-term debt, including securities due within one year, Carrying Amount	$ 26,156
Long-term debt, including securities due within one year, Fair Value	26,973
Alabama Power [Member]
Long-term debt:
Long-term debt, including securities due within one year, Carrying Amount	7,295
Long-term debt, including securities due within one year, Fair Value	7,621
Georgia Power [Member]
Long-term debt:
Long-term debt, including securities due within one year, Carrying Amount	10,379
Long-term debt, including securities due within one year, Fair Value	10,767
Gulf Power [Member]
Long-term debt:
Long-term debt, including securities due within one year, Carrying Amount	1,370
Long-term debt, including securities due within one year, Fair Value	1,438
Mississippi Power [Member]
Long-term debt:
Long-term debt, including securities due within one year, Carrying Amount	2,275
Long-term debt, including securities due within one year, Fair Value	2,246
Southern Power [Member]
Long-term debt:
Long-term debt, including securities due within one year, Carrying Amount	2,262
Long-term debt, including securities due within one year, Fair Value	$ 2,302

Fair Value Measurements - Narra

Fair Value Measurements - Narrative (Details) - Jun. 30, 2015 - USD ($) $ in Millions	Total	Total
Fair Value, Option, Quantitative Disclosures [Line Items]
Increase (decrease) in fair value of funds including reinvested interest and dividends	$ 44	$ 109
Georgia Power [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Notices Of Withdrawal Foreign Equity Funds	20.00%	20.00%
Increase (decrease) in fair value of funds including reinvested interest and dividends	$ (6)	$ 12
Georgia Power [Member] | Other - commingled funds [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Maximum Number of Days Related to Dollar Weighted Average Portfolio Maturities Regarding Commingled Funds		90 days
Georgia Power [Member] | Minimum [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Withdrawal Of Foreign Equity Fund Investment	1	$ 1
Foreign Equity Fund Investment	10	10
Alabama Power [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Increase (decrease) in fair value of funds including reinvested interest and dividends	$ 50	$ 97

Stockholders' Equity - Earnings

Stockholders' Equity - Earnings per Share (Details) - shares shares in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Earnings per Share
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	15	8	1	17
Southern Company [Member]
Earnings per Share
As reported shares	909	895	910	892
Effect of options and performance share award units	3	4	4	4
Diluted shares	912	899	914	896

Stockholders' Equity - Changes

Stockholders' Equity - Changes in Stockholders' Equity (Details) - USD ($) shares in Thousands, $ in Millions		3 Months Ended			6 Months Ended
		Jun. 30, 2015		Jun. 30, 2014	Jun. 30, 2015		Jun. 30, 2014
Changes in Stockholders' Equity
Beginning Balance					$ 20,926		$ 19,764
Net income after dividends on preferred and preference stock	[1]	$ 629	[2]	$ 611	1,138	[3]	962	[3]
Other comprehensive income (loss)					7		4
Treasury stock re-issued							216
Stock issued					117		161
Stock-based compensation					66
Stock repurchased, at cost					(115)		(5)
Cash dividends on common stock					(972)		(920)
Preference stock redemption					(150)
Contributions from noncontrolling interest					135
Distributions to noncontrolling interest					(5)
Net income attributable to noncontrolling interest					4
Other					(5)		0
Ending Balance		$ 21,146		$ 20,182	$ 21,146		$ 20,182
Number of Common shares Issued [Member]
Changes in Stockholders' Equity
Beginning Balance, Shares					908,502		892,733
Stock issued, Shares					3,222		3,898
Ending Balance, Shares		911,724		896,631	911,724		896,631
Number of Common shares Treasury [Member]
Changes in Stockholders' Equity
Beginning Balance, Shares					725		5,647
Treasury stock re-issued, Shares							4,739
Stock repurchased, at cost, Shares					(2,599)
Other, Shares					25		(27)
Ending Balance, Shares		3,299		935	3,299		935
Common Stockholders' Equity [Member]
Changes in Stockholders' Equity
Beginning Balance					$ 19,949		$ 19,008
Net income after dividends on preferred and preference stock					1,138		962
Other comprehensive income (loss)					7		4
Treasury stock re-issued							216
Stock issued					117		161
Stock-based compensation					$ 66
Stock repurchased, at cost, Shares					(2,600)
Stock repurchased, at cost					$ (115)		(5)
Cash dividends on common stock					(972)		(920)
Other					(8)		0
Ending Balance		$ 20,182		$ 19,426	20,182		19,426
Preferred And Preference Stock [Member]
Changes in Stockholders' Equity
Beginning Balance					756		756
Stock issued							0
Preference stock redemption					(150)
Other					3
Ending Balance		609		$ 756	609		$ 756
Noncontrolling Interest [Member]
Changes in Stockholders' Equity
Beginning Balance	[4]				221
Contributions from noncontrolling interest	[4]				135
Distributions to noncontrolling interest	[4]				(5)
Net income attributable to noncontrolling interest	[4]				4
Ending Balance	[4]	$ 355			$ 355
Stock Option Exercises Through December 2017 [Member]
Changes in Stockholders' Equity
Stock repurchased, at cost, Shares					(20,000)
[1]	After dividends on preferred and preference stock of subsidiaries.
[2]	Segment net income (loss) for the traditional operating companies for the three months ended June 30, 2015 includes a $23 million pre-tax charge ($14 million after tax) for estimated probable losses on the Kemper IGCC. See Note (B) under "Integrated Coal Gasification Combined Cycle – Kemper IGCC Schedule and Cost Estimate" herein for additional information.
[3]	Segment net income (loss) for the traditional operating companies for the six months ended June 30, 2015 and June 30, 2014 includes a $32 million pre-tax charge ($20 million after tax) and a $380 million pre-tax charge ($235 million after tax), respectively, for estimated probable losses on the Kemper IGCC. See Note (B) under "Integrated Coal Gasification Combined Cycle – Kemper IGCC Schedule and Cost Estimate" herein for additional information.
[4]	Primarily related to Southern Power Company.

Financing - Schedule of Credit

Financing - Schedule of Credit Arrangements (Details) $ in Millions	Jun. 30, 2015USD ($)
Line of Credit Facility [Line Items]
Expires, 2015	$ 239
Expires, 2016	799
Expires, 2017	30
Expires, 2018	4,130
Total	5,198
Unused	5,120
Executable Term Loans, One Year	158
Executable Term Loans, Two Years	40
Due Within One Year, Term Out	198
Due Within One Year, No Term Out	790
Southern Company [Member]
Line of Credit Facility [Line Items]
Expires, 2015	0
Expires, 2016	0
Expires, 2017	0
Expires, 2018	1,000
Total	1,000
Unused	1,000
Executable Term Loans, One Year	0
Executable Term Loans, Two Years	0
Due Within One Year, Term Out	0
Due Within One Year, No Term Out	0
Alabama Power [Member]
Line of Credit Facility [Line Items]
Expires, 2015	154
Expires, 2016	124
Expires, 2017	0
Expires, 2018	1,030
Total	1,308
Unused	1,307
Executable Term Loans, One Year	58
Executable Term Loans, Two Years	0
Due Within One Year, Term Out	58
Due Within One Year, No Term Out	170
Georgia Power [Member]
Line of Credit Facility [Line Items]
Expires, 2015	0
Expires, 2016	150
Expires, 2017	0
Expires, 2018	1,600
Total	1,750
Unused	1,737
Executable Term Loans, One Year	0
Executable Term Loans, Two Years	0
Due Within One Year, Term Out	0
Due Within One Year, No Term Out	150
Gulf Power [Member]
Line of Credit Facility [Line Items]
Expires, 2015	20
Expires, 2016	225
Expires, 2017	30
Expires, 2018	0
Total	275
Unused	275
Executable Term Loans, One Year	50
Executable Term Loans, Two Years	0
Due Within One Year, Term Out	50
Due Within One Year, No Term Out	195
Mississippi Power [Member]
Line of Credit Facility [Line Items]
Expires, 2015	40
Expires, 2016	255
Expires, 2017	0
Expires, 2018	0
Total	295
Unused	265
Executable Term Loans, One Year	30
Executable Term Loans, Two Years	40
Due Within One Year, Term Out	70
Due Within One Year, No Term Out	225
Southern Power [Member]
Line of Credit Facility [Line Items]
Expires, 2015	0
Expires, 2016	0
Expires, 2017	0
Expires, 2018	500
Total	500
Unused	466
Executable Term Loans, One Year	0
Executable Term Loans, Two Years	0
Due Within One Year, Term Out	0
Due Within One Year, No Term Out	0
Other Subsidiaries [Member]
Line of Credit Facility [Line Items]
Expires, 2015	25
Expires, 2016	45
Expires, 2017	0
Expires, 2018	0
Total	70
Unused	70
Executable Term Loans, One Year	20
Executable Term Loans, Two Years	0
Due Within One Year, Term Out	20
Due Within One Year, No Term Out	$ 50

Financing - Schedule of Long-Te

Financing - Schedule of Long-Term Debt Financing Activities (Details) - USD ($) $ in Millions		1 Months Ended	3 Months Ended	6 Months Ended
		May. 31, 2015	Jun. 30, 2015	Jun. 30, 2015
Debt Instrument [Line Items]
Senior Note Issuances	[1]			$ 2,225
Senior Note Redemptions	[1]			375
Revenue Bond Issuances and Reofferings of Purchased Bonds	[1],[2]			250
Revenue Bond Maturities and Repurchases	[1]			199
Other Long-Term Debt Issuances	[1]			600
Other Long-Term Debt Redemptions and Maturities	[1],[3]			365
Southern Company [Member]
Debt Instrument [Line Items]
Senior Note Issuances	[1]			600
Senior Note Redemptions	[1]			0
Revenue Bond Issuances and Reofferings of Purchased Bonds	[1],[2]			0
Revenue Bond Maturities and Repurchases	[1]			0
Other Long-Term Debt Issuances	[1]			0
Other Long-Term Debt Redemptions and Maturities	[1],[3]			0
Alabama Power [Member]
Debt Instrument [Line Items]
Senior Note Issuances	[1]			975
Senior Note Redemptions	[1]			250
Revenue Bond Issuances and Reofferings of Purchased Bonds	[1],[2]			80
Revenue Bond Maturities and Repurchases	[1]			134
Other Long-Term Debt Issuances	[1]			0
Other Long-Term Debt Redemptions and Maturities	[1],[3]			0
Revenue Bond Issuances			$ 80
Georgia Power [Member]
Debt Instrument [Line Items]
Senior Note Issuances	[1]			0
Senior Note Redemptions	[1]			125
Revenue Bond Issuances and Reofferings of Purchased Bonds	[1],[2]			170
Revenue Bond Maturities and Repurchases	[1]			65
Other Long-Term Debt Issuances	[1]			600
Other Long-Term Debt Redemptions and Maturities	[1],[3]			5
Mississippi Power [Member]
Debt Instrument [Line Items]
Senior Note Issuances	[1]			0
Senior Note Redemptions	[1]			0
Revenue Bond Issuances and Reofferings of Purchased Bonds	[1],[2]			0
Revenue Bond Maturities and Repurchases	[1]			0
Other Long-Term Debt Issuances	[1]			0
Other Long-Term Debt Redemptions and Maturities	[1],[3]			351
Southern Power [Member]
Debt Instrument [Line Items]
Senior Note Issuances	[1]			650
Senior Note Redemptions	[1]			0
Revenue Bond Issuances and Reofferings of Purchased Bonds	[1],[2]			0
Revenue Bond Maturities and Repurchases	[1]			0
Other Long-Term Debt Issuances	[1]			0
Other Long-Term Debt Redemptions and Maturities	[1],[3]			0
Other Subsidiaries [Member]
Debt Instrument [Line Items]
Senior Note Issuances	[1]			0
Senior Note Redemptions	[1]			0
Revenue Bond Issuances and Reofferings of Purchased Bonds	[1],[2]			0
Revenue Bond Maturities and Repurchases	[1]			0
Other Long-Term Debt Issuances	[1]			0
Other Long-Term Debt Redemptions and Maturities	[1],[3]			9
Debt Held Since 2013 [Member] | Georgia Power [Member]
Debt Instrument [Line Items]
Revenue Bond Issuances		$ 104.6		104.6
Debt Held Since 2015 [Member] | Georgia Power [Member]
Debt Instrument [Line Items]
Revenue Bond Issuances				$ 65
[1]	Gulf Power did not issue or redeem any long-term debt during the first six months of 2015.
[2]	Includes reoffering by Alabama Power of $80 million aggregate principal amount of revenue bonds previously purchased and held by Alabama Power since April 2015 and reofferings by Georgia Power of $104.6 million and $65 million aggregate principal amount of revenue bonds previously purchased and held by Georgia Power since 2013 and April 2015, respectively
[3]	Includes reductions in capital lease obligations resulting from cash payments under capital leases.

Financing - Narrative (Details)

Financing - Narrative (Details) $ / shares in Units, shares in Thousands	Jul. 15, 2015USD ($)	Jun. 03, 2015USD ($)	Jun. 30, 2015USD ($)	May. 31, 2015USD ($)$ / sharesshares	Apr. 30, 2015USD ($)loan	Jun. 30, 2015USD ($)	Jun. 30, 2015USD ($)	Jun. 30, 2014USD ($)	Mar. 31, 2015USD ($)
Debt Instrument [Line Items]
Amount of Variable Rate Pollution Control Revenue Bonds Outstanding Requiring Liquidity Support			$ 1,900,000,000			$ 1,900,000,000	$ 1,900,000,000
Derivative, Notional Amount			2,000,000,000			2,000,000,000	2,000,000,000
Alabama Power [Member]
Debt Instrument [Line Items]
Amount of Variable Rate Pollution Control Revenue Bonds Outstanding Requiring Liquidity Support			810,000,000			810,000,000	810,000,000
Amount of Fixed Rate Pollution Control Revenue Bonds Outstanding Requiring Liquidity Support			200,000,000			200,000,000	200,000,000
Remarketing Revenue Bond						80,000,000
Repayments of Senior Debt							250,000,000	$ 0
Alabama Power [Member] | Five Point Two Zero Percent Class A Preferred Stock [Member]
Debt Instrument [Line Items]
Temporary Equity, Shares Outstanding | shares				6,480
Temporary Equity, Dividend Rate Percentage				0.052
Redemption price (in dollars per share) | $ / shares				$ 25
Alabama Power [Member] | Five Point Three Zero Percent Class A Preferred Stock [Member]
Debt Instrument [Line Items]
Temporary Equity, Shares Outstanding | shares				4,000
Temporary Equity, Dividend Rate Percentage				0.053
Redemption price (in dollars per share) | $ / shares				$ 25
Alabama Power [Member] | Five Point Six Two Five Percent Preference Stock [Member]
Debt Instrument [Line Items]
Temporary Equity, Shares Outstanding | shares				6,000
Temporary Equity, Dividend Rate Percentage				0.05625
Redemption price (in dollars per share) | $ / shares				$ 25
Alabama Power [Member] | Unsecured Debt [Member]
Debt Instrument [Line Items]
Redemption Amount Of Principal Notes									$ 250,000,000
Alabama Power [Member] | Series DD [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage									5.65%
Alabama Power [Member] | Series 2015A [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount					$ 175,000,000				$ 550,000,000
Debt Instrument, Interest Rate, Stated Percentage					3.75%				3.75%
Alabama Power [Member] | Series 2007B [Member]
Debt Instrument [Line Items]
Remarketing Revenue Bond					$ 80,000,000
Alabama Power [Member] | Series 2015B [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount					$ 250,000,000
Debt Instrument, Interest Rate, Stated Percentage					2.80%
Alabama Power [Member] | Aggregate Stated Capital [Member] | Five Point Two Zero Percent Class A Preferred Stock [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount				$ 162,000,000
Alabama Power [Member] | Aggregate Stated Capital [Member] | Five Point Three Zero Percent Class A Preferred Stock [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount				100,000,000
Alabama Power [Member] | Aggregate Stated Capital [Member] | Five Point Six Two Five Percent Preference Stock [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount				150,000,000
Georgia Power [Member]
Debt Instrument [Line Items]
Amount of Variable Rate Pollution Control Revenue Bonds Outstanding Requiring Liquidity Support			970,000,000			970,000,000	970,000,000
Amount of Fixed Rate Pollution Control Revenue Bonds Outstanding Requiring Liquidity Support			122,000,000			122,000,000	122,000,000
Line of Credit Facility, Current Borrowing Capacity			600,000,000			600,000,000	$ 600,000,000
Period Of Amortization Of Gain (Loss) On Settlement Of Derivatives							10 years
Repayments of Senior Debt							$ 125,000,000	0
Georgia Power [Member] | Interest Rate Swap [Member]
Debt Instrument [Line Items]
Gain (Loss) on Settlement Of Derivatives			(6,000,000)			(6,000,000)	(6,000,000)
Georgia Power [Member] | Maturity Date May 2025 [Member] | Cash Flow Hedges Of Forecasted Debt [Member] | Interest Rate Swap [Member]
Debt Instrument [Line Items]
Derivative, Notional Amount			$ 350,000,000			$ 350,000,000	350,000,000
Georgia Power [Member] | Second Series 2008 [Member]
Debt Instrument [Line Items]
Long-term Pollution Control Bond					$ 65,000,000
Georgia Power [Member] | Debt Held Since 2013 [Member]
Debt Instrument [Line Items]
Remarketing Revenue Bond				104,600,000			$ 104,600,000
Georgia Power [Member] | Debt Due Two Thousand Forty Four [Member] | Line of Credit [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			3.283%			3.283%	3.283%
Gulf Power [Member]
Debt Instrument [Line Items]
Amount of Variable Rate Pollution Control Revenue Bonds Outstanding Requiring Liquidity Support			$ 69,000,000			$ 69,000,000	$ 69,000,000
Amount of Fixed Rate Pollution Control Revenue Bonds Outstanding Requiring Liquidity Support			46,000,000			46,000,000	46,000,000
Mississippi Power [Member]
Debt Instrument [Line Items]
Amount of Variable Rate Pollution Control Revenue Bonds Outstanding Requiring Liquidity Support			$ 40,000,000			40,000,000	40,000,000
Number Of Floating Rate Bank Loans | loan					3
Aggregate Principal Amount Of Floating Rate Bank Loan					$ 475,000,000
Debt Instrument, Description of Variable Rate Basis			one-month LIBOR		one-month LIBOR
Repayment Aggregate Principal Amount Of Floating Rate Bank Loan					$ 275,000,000
Bank Loans Period Of Extension		18 months	18 months
Promissory Note		$ 301,000,000	$ 301,000,000				301,000,000	$ 0
Mississippi Power [Member] | Maturity April First Two Thousand Sixteen [Member]
Debt Instrument [Line Items]
Number Of Floating Rate Bank Loans | loan					2
Aggregate Principal Amount Of Floating Rate Bank Loan					$ 425,000,000
Traditional Operating Companies [Member]
Debt Instrument [Line Items]
Amount of Fixed Rate Pollution Control Revenue Bonds Outstanding Requiring Liquidity Support			368,000,000			368,000,000	368,000,000
Southern Company [Member] | Series 2015A [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount			$ 600,000,000			$ 600,000,000	$ 600,000,000
Debt Instrument, Interest Rate, Stated Percentage			2.75%			2.75%	2.75%
Southern Power [Member] | Series 2015A [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount				$ 350,000,000
Debt Instrument, Interest Rate, Stated Percentage				1.50%
Southern Power [Member] | Series 2015B [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount				$ 300,000,000
Debt Instrument, Interest Rate, Stated Percentage				2.375%
Subsequent Event [Member] | Southern Power [Member] | Series Two Thousand Three [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	4.875%
Repayments of Senior Debt	$ 525,000,000

Retirement Benefits (Details)

Retirement Benefits (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Pension Plans [Member] | Southern Company [Member]
Pension Plans and Postretirement Plans
Service cost	$ 64	$ 54	$ 128	$ 107
Interest cost	111	108	222	217
Expected return on plan assets	(181)	(162)	(362)	(323)
Amortization:
Prior service costs	7	7	13	13
Net (gain)/loss	54	27	108	55
Net cost	55	34	109	69
Pension Plans [Member] | Alabama Power [Member]
Pension Plans and Postretirement Plans
Service cost	15	12	30	24
Interest cost	27	26	53	52
Expected return on plan assets	(44)	(42)	(89)	(84)
Amortization:
Prior service costs	1	2	3	3
Net (gain)/loss	13	8	27	16
Net cost	12	6	24	11
Pension Plans [Member] | Georgia Power [Member]
Pension Plans and Postretirement Plans
Service cost	18	15	36	31
Interest cost	39	38	77	76
Expected return on plan assets	(63)	(56)	(126)	(113)
Amortization:
Prior service costs	2	2	5	5
Net (gain)/loss	19	10	38	20
Net cost	15	9	30	19
Pension Plans [Member] | Gulf Power [Member]
Pension Plans and Postretirement Plans
Service cost	3	1	6	4
Interest cost	5	5	10	10
Expected return on plan assets	(8)	(7)	(16)	(14)
Amortization:
Prior service costs	0	1	0	1
Net (gain)/loss	2	1	5	2
Net cost	2	1	5	3
Pension Plans [Member] | Mississippi Power [Member]
Pension Plans and Postretirement Plans
Service cost	3	2	6	5
Interest cost	6	5	11	10
Expected return on plan assets	(9)	(7)	(17)	(14)
Amortization:
Prior service costs	1	1	1	1
Net (gain)/loss	2	1	5	2
Net cost	3	2	6	4
Other Postretirement Benefits [Member] | Southern Company [Member]
Pension Plans and Postretirement Plans
Service cost	5	6	11	11
Interest cost	20	20	39	40
Expected return on plan assets	(14)	(15)	(29)	(30)
Amortization:
Prior service costs	1	1	2	2
Net (gain)/loss	4	0	9	1
Net cost	16	12	32	24
Other Postretirement Benefits [Member] | Alabama Power [Member]
Pension Plans and Postretirement Plans
Service cost	2	2	3	3
Interest cost	5	5	10	10
Expected return on plan assets	(7)	(7)	(13)	(13)
Amortization:
Prior service costs	0	1	1	2
Net (gain)/loss	1	0	1	0
Net cost	1	1	2	2
Other Postretirement Benefits [Member] | Georgia Power [Member]
Pension Plans and Postretirement Plans
Service cost	1	1	3	3
Interest cost	9	9	17	17
Expected return on plan assets	(6)	(7)	(12)	(13)
Amortization:
Prior service costs	0	0	0	0
Net (gain)/loss	3	1	6	1
Net cost	7	4	14	8
Other Postretirement Benefits [Member] | Gulf Power [Member]
Pension Plans and Postretirement Plans
Service cost	0	1	0	1
Interest cost	1	1	2	2
Expected return on plan assets	(1)	(1)	(1)	(1)
Amortization:
Prior service costs	0	0	0	0
Net (gain)/loss	0	0	0	0
Net cost	0	1	1	2
Other Postretirement Benefits [Member] | Mississippi Power [Member]
Pension Plans and Postretirement Plans
Service cost	1	1	1	1
Interest cost	1	1	2	2
Expected return on plan assets	(1)	(1)	(1)	(1)
Amortization:
Prior service costs	0	0	0	0
Net (gain)/loss	0	0	0	0
Net cost	$ 1	$ 1	$ 2	$ 2

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Income Tax Contingency [Line Items]
Operating loss carryforwards	$ 24
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Unrecognized tax benefits as of December 31, 2014	170
Tax positions from current periods	2
Tax positions from prior periods	231
Reductions due to settlements	(5)
Balance as of June 30, 2015	398
Tax positions impacting the effective tax rate	8		$ 10
Tax positions not impacting the effective tax rate	390		160
Kemper Igcc [Member]
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance as of June 30, 2015	390
Unrecognized tax benefit, associated interest	$ 5
Mississippi Power [Member]
Income Tax Contingency [Line Items]
Effective tax rate	19.00%	(51.10%)
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Unrecognized tax benefits as of December 31, 2014	$ 165
Tax positions from current periods	0
Tax positions from prior periods	230
Reductions due to settlements	(5)
Balance as of June 30, 2015	390
Tax positions impacting the effective tax rate	0
Tax positions not impacting the effective tax rate	390
Mississippi Power [Member] | Kemper Igcc [Member]
Income Tax Contingency [Line Items]
Unrecognized Tax Benefits, Interest on Income Taxes Expense	5
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance as of June 30, 2015	390
Southern Power [Member]
Income Tax Contingency [Line Items]
Operating loss carryforwards	$ 428		$ 305
Effective tax rate	13.70%	0.30%
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Unrecognized tax benefits as of December 31, 2014	$ 5
Tax positions from current periods	2
Tax positions from prior periods	0
Reductions due to settlements	0
Balance as of June 30, 2015	7
Tax positions impacting the effective tax rate	7
Tax positions not impacting the effective tax rate	$ 0

Derivatives - Schedule of Deriv

Derivatives - Schedule of Derivatives and Gains (Losses) (Details) - Jun. 30, 2015 BTU in Millions, $ in Millions	USD ($)BTU
Notional amount of interest rate derivatives
Notional Amount	$ 2,000
Fair Value Gain (Loss) at June 30, 2015	(3)
Southern Company [Member] | Maturity Date August 2017 [Member] | Fair Value Hedges Of Existing Debt [Member]
Notional amount of interest rate derivatives
Notional Amount	$ 250
Interest Rate Received	1.30%
Weighted Average Interest Rate Paid	0.17%
Weighted Average Interest Rate Paid, Description	3-month LIBOR + 0.17%
Hedge Maturity Date	Aug. 1, 2017
Fair Value Gain (Loss) at June 30, 2015	$ 2
Southern Company [Member] | Maturity Date June 2020 [Member] | Fair Value Hedges Of Existing Debt [Member]
Notional amount of interest rate derivatives
Notional Amount	$ 300
Interest Rate Received	2.75%
Weighted Average Interest Rate Paid	0.92%
Weighted Average Interest Rate Paid, Description	3-month LIBOR + 0.92%
Hedge Maturity Date	Jun. 1, 2020
Fair Value Gain (Loss) at June 30, 2015	$ 1
Southern Company [Member] | Gas [Member]
Energy-related derivative contracts
Net Purchased mmBtu | BTU	220
Longest Hedge Date	2,020
Longest Non-Hedge Date	2,017
Alabama Power [Member] | Maturity Date October 2025 [Member] | Cash Flow Hedges Of Forecasted Debt [Member]
Notional amount of interest rate derivatives
Notional Amount	$ 200
Interest Rate Received, Description	3-month LIBOR
Weighted Average Interest Rate Paid	2.93%
Hedge Maturity Date	Oct. 1, 2025
Fair Value Gain (Loss) at June 30, 2015	$ (7)
Alabama Power [Member] | Gas [Member]
Energy-related derivative contracts
Net Purchased mmBtu | BTU	49
Longest Hedge Date	2,018
Georgia Power [Member] | Maturity Date November 2025 [Member] | Cash Flow Hedges Of Forecasted Debt [Member]
Notional amount of interest rate derivatives
Notional Amount	$ 350
Interest Rate Received, Description	3-month LIBOR
Weighted Average Interest Rate Paid	2.57%
Hedge Maturity Date	Nov. 1, 2025
Fair Value Gain (Loss) at June 30, 2015	$ (1)
Georgia Power [Member] | Maturity Date March 2016 [Member] | Cash Flow Hedges Of Existing Debt [Member]
Notional amount of interest rate derivatives
Notional Amount	$ 250
Interest Rate Received, Description	3-month LIBOR + 0.32%
Interest Rate Received	0.32%
Weighted Average Interest Rate Paid	0.75%
Hedge Maturity Date	Mar. 1, 2016
Fair Value Gain (Loss) at June 30, 2015	$ 0
Georgia Power [Member] | Maturity Date August 2016 [Member] | Cash Flow Hedges Of Existing Debt [Member]
Notional amount of interest rate derivatives
Notional Amount	$ 200
Interest Rate Received, Description	3-month LIBOR + 0.40%
Interest Rate Received	0.40%
Weighted Average Interest Rate Paid	1.01%
Hedge Maturity Date	Aug. 1, 2016
Fair Value Gain (Loss) at June 30, 2015	$ 0
Georgia Power [Member] | Maturity Date June 2018 [Member] | Fair Value Hedges Of Existing Debt [Member]
Notional amount of interest rate derivatives
Notional Amount	$ 250
Interest Rate Received	5.40%
Weighted Average Interest Rate Paid	4.02%
Weighted Average Interest Rate Paid, Description	3-month LIBOR + 4.02%
Hedge Maturity Date	Jun. 1, 2018
Fair Value Gain (Loss) at June 30, 2015	$ 1
Georgia Power [Member] | Maturity Date December 2019 [Member] | Fair Value Hedges Of Existing Debt [Member]
Notional amount of interest rate derivatives
Notional Amount	$ 200
Interest Rate Received	4.25%
Weighted Average Interest Rate Paid	2.46%
Weighted Average Interest Rate Paid, Description	3-month LIBOR + 2.46%
Hedge Maturity Date	Dec. 1, 2019
Fair Value Gain (Loss) at June 30, 2015	$ 1
Georgia Power [Member] | Gas [Member]
Energy-related derivative contracts
Net Purchased mmBtu | BTU	47
Longest Hedge Date	2,017
Gulf Power [Member] | Gas [Member]
Energy-related derivative contracts
Net Purchased mmBtu | BTU	80
Longest Hedge Date	2,020
Mississippi Power [Member] | Gas [Member]
Energy-related derivative contracts
Net Purchased mmBtu | BTU	43
Longest Hedge Date	2,018
Southern Power [Member] | Gas [Member]
Energy-related derivative contracts
Net Purchased mmBtu | BTU	1
Longest Hedge Date	2,015
Longest Non-Hedge Date	2,017

Derivatives - Balance Sheet Pre

Derivatives - Balance Sheet Presentation (Details) - USD ($) $ in Millions	Jun. 30, 2015		Dec. 31, 2014
Not Designated as Hedging Instrument [Member] | Energy Related Derivative [Member] | Other current assets [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives			$ 6
Southern Company [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives	$ 16		21
Energy-related derivatives	194		225
Southern Company [Member] | Not Designated as Hedging Instrument [Member] | Energy Related Derivative [Member] | Other current liabilities [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives			4
Alabama Power [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives	2		1
Energy-related derivatives	55		61
Alabama Power [Member] | Not Designated as Hedging Instrument [Member] | Energy Related Derivative [Member] | Other current assets [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives			0
Alabama Power [Member] | Not Designated as Hedging Instrument [Member] | Energy Related Derivative [Member] | Other current liabilities [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives			0
Georgia Power [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives	8		13
Energy-related derivatives	21		41
Georgia Power [Member] | Not Designated as Hedging Instrument [Member] | Energy Related Derivative [Member] | Other current assets [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives			0
Georgia Power [Member] | Not Designated as Hedging Instrument [Member] | Energy Related Derivative [Member] | Other current liabilities [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives			0
Gulf Power [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives	0		0
Energy-related derivatives	74		72
Gulf Power [Member] | Not Designated as Hedging Instrument [Member] | Energy Related Derivative [Member] | Other current assets [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives			0
Gulf Power [Member] | Not Designated as Hedging Instrument [Member] | Energy Related Derivative [Member] | Other current liabilities [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives			0
Mississippi Power [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives	0		0
Energy-related derivatives	41		45
Mississippi Power [Member] | Not Designated as Hedging Instrument [Member] | Energy Related Derivative [Member] | Other current assets [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives			0
Mississippi Power [Member] | Not Designated as Hedging Instrument [Member] | Energy Related Derivative [Member] | Other current liabilities [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives			0
Southern Power [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives	0		5
Energy-related derivatives	0		4
Southern Power [Member] | Not Designated as Hedging Instrument [Member] | Energy Related Derivative [Member] | Other current assets [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives			5
Southern Power [Member] | Not Designated as Hedging Instrument [Member] | Energy Related Derivative [Member] | Other current liabilities [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives			4
Hedging Instruments for Regulatory Purposes [Member] | Southern Company [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives			7
Energy-related derivatives	180		197
Hedging Instruments for Regulatory Purposes [Member] | Southern Company [Member] | Energy Related Derivative [Member] | Other current assets [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives	5		7
Hedging Instruments for Regulatory Purposes [Member] | Southern Company [Member] | Energy Related Derivative [Member] | Other deferred charges and assets [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives			0
Hedging Instruments for Regulatory Purposes [Member] | Southern Company [Member] | Energy Related Derivative [Member] | Other current liabilities [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives	99	[1]	118	[2]
Hedging Instruments for Regulatory Purposes [Member] | Southern Company [Member] | Energy Related Derivative [Member] | Other deferred credits and liabilities [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives	81		79
Hedging Instruments for Regulatory Purposes [Member] | Alabama Power [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives			1
Energy-related derivatives	48		53
Hedging Instruments for Regulatory Purposes [Member] | Alabama Power [Member] | Energy Related Derivative [Member] | Other current assets [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives	2		1
Hedging Instruments for Regulatory Purposes [Member] | Alabama Power [Member] | Energy Related Derivative [Member] | Other deferred charges and assets [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives			0
Hedging Instruments for Regulatory Purposes [Member] | Alabama Power [Member] | Energy Related Derivative [Member] | Other current liabilities [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives	31	[1]	32	[2]
Hedging Instruments for Regulatory Purposes [Member] | Alabama Power [Member] | Energy Related Derivative [Member] | Other deferred credits and liabilities [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives	17		21
Hedging Instruments for Regulatory Purposes [Member] | Georgia Power [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives			7
Energy-related derivatives	17		27
Hedging Instruments for Regulatory Purposes [Member] | Georgia Power [Member] | Energy Related Derivative [Member] | Other current assets [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives	3		6
Hedging Instruments for Regulatory Purposes [Member] | Georgia Power [Member] | Energy Related Derivative [Member] | Other deferred charges and assets [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives			1
Hedging Instruments for Regulatory Purposes [Member] | Georgia Power [Member] | Energy Related Derivative [Member] | Other current liabilities [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives	15	[1]	23	[2]
Hedging Instruments for Regulatory Purposes [Member] | Georgia Power [Member] | Energy Related Derivative [Member] | Other deferred credits and liabilities [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives	2		4
Hedging Instruments for Regulatory Purposes [Member] | Gulf Power [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives			0
Energy-related derivatives	74		72
Hedging Instruments for Regulatory Purposes [Member] | Gulf Power [Member] | Energy Related Derivative [Member] | Other current assets [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives	0		0
Hedging Instruments for Regulatory Purposes [Member] | Gulf Power [Member] | Energy Related Derivative [Member] | Other deferred charges and assets [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives			0
Hedging Instruments for Regulatory Purposes [Member] | Gulf Power [Member] | Energy Related Derivative [Member] | Other current liabilities [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives	32	[1]	37	[2]
Hedging Instruments for Regulatory Purposes [Member] | Gulf Power [Member] | Energy Related Derivative [Member] | Other deferred credits and liabilities [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives	42		35
Hedging Instruments for Regulatory Purposes [Member] | Mississippi Power [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives			0
Energy-related derivatives	41		45
Hedging Instruments for Regulatory Purposes [Member] | Mississippi Power [Member] | Energy Related Derivative [Member] | Other current assets [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives	0		0
Hedging Instruments for Regulatory Purposes [Member] | Mississippi Power [Member] | Energy Related Derivative [Member] | Other deferred charges and assets [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives			0
Hedging Instruments for Regulatory Purposes [Member] | Mississippi Power [Member] | Energy Related Derivative [Member] | Other current liabilities [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives	21	[1]	26	[2]
Hedging Instruments for Regulatory Purposes [Member] | Mississippi Power [Member] | Energy Related Derivative [Member] | Other deferred credits and liabilities [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives	20		19
Cash Flow and Fair Value Hedging [Member] | Southern Company [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives			8
Cash Flow and Fair Value Hedging [Member] | Southern Company [Member] | Interest Rate Contract [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives	14		24
Cash Flow and Fair Value Hedging [Member] | Southern Company [Member] | Interest Rate Contract [Member] | Other current assets [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives	11		7
Cash Flow and Fair Value Hedging [Member] | Southern Company [Member] | Interest Rate Contract [Member] | Other deferred charges and assets [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives			1
Cash Flow and Fair Value Hedging [Member] | Southern Company [Member] | Interest Rate Contract [Member] | Other current liabilities [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives	8	[1]	17	[2]
Cash Flow and Fair Value Hedging [Member] | Southern Company [Member] | Interest Rate Contract [Member] | Other deferred credits and liabilities [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives	6		7
Cash Flow and Fair Value Hedging [Member] | Alabama Power [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives			0
Cash Flow and Fair Value Hedging [Member] | Alabama Power [Member] | Interest Rate Contract [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives	7		8
Cash Flow and Fair Value Hedging [Member] | Alabama Power [Member] | Interest Rate Contract [Member] | Other current assets [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives	0		0
Cash Flow and Fair Value Hedging [Member] | Alabama Power [Member] | Interest Rate Contract [Member] | Other deferred charges and assets [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives			0
Cash Flow and Fair Value Hedging [Member] | Alabama Power [Member] | Interest Rate Contract [Member] | Other current liabilities [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives	7	[1]	8	[2]
Cash Flow and Fair Value Hedging [Member] | Alabama Power [Member] | Interest Rate Contract [Member] | Other deferred credits and liabilities [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives	0		0
Cash Flow and Fair Value Hedging [Member] | Georgia Power [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives			6
Cash Flow and Fair Value Hedging [Member] | Georgia Power [Member] | Interest Rate Contract [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives	4		14
Cash Flow and Fair Value Hedging [Member] | Georgia Power [Member] | Interest Rate Contract [Member] | Other current assets [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives	5		5
Cash Flow and Fair Value Hedging [Member] | Georgia Power [Member] | Interest Rate Contract [Member] | Other deferred charges and assets [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives			1
Cash Flow and Fair Value Hedging [Member] | Georgia Power [Member] | Interest Rate Contract [Member] | Other current liabilities [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives	1	[1]	9	[2]
Cash Flow and Fair Value Hedging [Member] | Georgia Power [Member] | Interest Rate Contract [Member] | Other deferred credits and liabilities [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives	3		5
Cash Flow and Fair Value Hedging [Member] | Gulf Power [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives			0
Cash Flow and Fair Value Hedging [Member] | Gulf Power [Member] | Interest Rate Contract [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives	0		0
Cash Flow and Fair Value Hedging [Member] | Gulf Power [Member] | Interest Rate Contract [Member] | Other current assets [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives	0		0
Cash Flow and Fair Value Hedging [Member] | Gulf Power [Member] | Interest Rate Contract [Member] | Other deferred charges and assets [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives			0
Cash Flow and Fair Value Hedging [Member] | Gulf Power [Member] | Interest Rate Contract [Member] | Other current liabilities [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives	0	[1]	0	[2]
Cash Flow and Fair Value Hedging [Member] | Gulf Power [Member] | Interest Rate Contract [Member] | Other deferred credits and liabilities [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives	0		0
Cash Flow and Fair Value Hedging [Member] | Mississippi Power [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives			0
Cash Flow and Fair Value Hedging [Member] | Mississippi Power [Member] | Interest Rate Contract [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives	0		0
Cash Flow and Fair Value Hedging [Member] | Mississippi Power [Member] | Interest Rate Contract [Member] | Other current assets [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives	0		0
Cash Flow and Fair Value Hedging [Member] | Mississippi Power [Member] | Interest Rate Contract [Member] | Other deferred charges and assets [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives			0
Cash Flow and Fair Value Hedging [Member] | Mississippi Power [Member] | Interest Rate Contract [Member] | Other current liabilities [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives	0	[1]	0	[2]
Cash Flow and Fair Value Hedging [Member] | Mississippi Power [Member] | Interest Rate Contract [Member] | Other deferred credits and liabilities [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives	0		0
Cash Flow and Fair Value Hedging [Member] | Southern Power [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives			0
Cash Flow and Fair Value Hedging [Member] | Southern Power [Member] | Interest Rate Contract [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives	0		0
Cash Flow and Fair Value Hedging [Member] | Southern Power [Member] | Interest Rate Contract [Member] | Other current assets [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives	0		0
Cash Flow and Fair Value Hedging [Member] | Southern Power [Member] | Interest Rate Contract [Member] | Other deferred charges and assets [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives			0
Cash Flow and Fair Value Hedging [Member] | Southern Power [Member] | Interest Rate Contract [Member] | Other current liabilities [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives	0	[1]	0	[2]
Cash Flow and Fair Value Hedging [Member] | Southern Power [Member] | Interest Rate Contract [Member] | Other deferred credits and liabilities [Member]
Derivatives, Fair Value [Line Items]
Energy-related derivatives	$ 0		$ 0
[1]	Gulf Power includes current liabilities related to derivatives designated as hedging instruments in "Liabilities from risk management activities."
[2]	Gulf Power includes current liabilities related to derivatives designated as hedging instruments in "Liabilities from risk management activities."

Derivatives - Balance Sheet Off

Derivatives - Balance Sheet Offsetting (Details) - USD ($) $ in Millions	Jun. 30, 2015		Dec. 31, 2014
Southern Company [Member]
Derivative [Line Items]
Energy-related derivatives	$ 16		$ 21
Energy-related derivatives	194		225
Southern Company [Member] | Energy Related Derivative [Member]
Derivative [Line Items]
Derivative Asset, Fair Value, Amount Offset Against Collateral	0		4
Derivative Liability, Fair Value, Amount Offset Against Collateral	175		192
Southern Company [Member] | Energy Related Derivative [Member] | Net Amount Of Derivatives [Member]
Derivative [Line Items]
Energy-related derivatives	5	[1]	13	[2]
Energy-related derivatives	180	[1]	201	[2]
Southern Company [Member] | Energy Related Derivative [Member] | Gross Amount Of Derivatives [Member]
Derivative [Line Items]
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	(5)	[3]	(9)	[4]
Derivative Liability, Fair Value, Amount Not Offset Against Collateral	(5)	[3]	(9)	[4]
Southern Company [Member] | Interest Rate Contract [Member]
Derivative [Line Items]
Derivative Asset, Fair Value, Amount Offset Against Collateral	3		0
Derivative Liability, Fair Value, Amount Offset Against Collateral	6		16
Southern Company [Member] | Interest Rate Contract [Member] | Net Amount Of Derivatives [Member]
Derivative [Line Items]
Energy-related derivatives	11	[1]	8	[2]
Energy-related derivatives	14	[1]	24	[2]
Southern Company [Member] | Interest Rate Contract [Member] | Gross Amount Of Derivatives [Member]
Derivative [Line Items]
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	(8)	[3]	(8)	[4]
Derivative Liability, Fair Value, Amount Not Offset Against Collateral	(8)	[3]	(8)	[4]
Alabama Power [Member]
Derivative [Line Items]
Energy-related derivatives	2		1
Energy-related derivatives	55		61
Alabama Power [Member] | Energy Related Derivative [Member]
Derivative [Line Items]
Derivative Asset, Fair Value, Amount Offset Against Collateral	0		1
Derivative Liability, Fair Value, Amount Offset Against Collateral	46		53
Alabama Power [Member] | Energy Related Derivative [Member] | Net Amount Of Derivatives [Member]
Derivative [Line Items]
Energy-related derivatives	2	[1]	1	[2]
Energy-related derivatives	48	[1]	53	[2]
Alabama Power [Member] | Energy Related Derivative [Member] | Gross Amount Of Derivatives [Member]
Derivative [Line Items]
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	(2)	[3]	0	[4]
Derivative Liability, Fair Value, Amount Not Offset Against Collateral	(2)	[3]	0	[4]
Alabama Power [Member] | Interest Rate Contract [Member]
Derivative [Line Items]
Derivative Asset, Fair Value, Amount Offset Against Collateral	0		0
Derivative Liability, Fair Value, Amount Offset Against Collateral	7		8
Alabama Power [Member] | Interest Rate Contract [Member] | Net Amount Of Derivatives [Member]
Derivative [Line Items]
Energy-related derivatives	0	[1]	0	[2]
Energy-related derivatives	7	[1]	8	[2]
Alabama Power [Member] | Interest Rate Contract [Member] | Gross Amount Of Derivatives [Member]
Derivative [Line Items]
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	0	[3]	0	[4]
Derivative Liability, Fair Value, Amount Not Offset Against Collateral	0	[3]	0	[4]
Georgia Power [Member]
Derivative [Line Items]
Energy-related derivatives	8		13
Energy-related derivatives	21		41
Georgia Power [Member] | Energy Related Derivative [Member]
Derivative [Line Items]
Derivative Asset, Fair Value, Amount Offset Against Collateral	0		0
Derivative Liability, Fair Value, Amount Offset Against Collateral	14		20
Georgia Power [Member] | Energy Related Derivative [Member] | Net Amount Of Derivatives [Member]
Derivative [Line Items]
Energy-related derivatives	3	[1]	7	[2]
Energy-related derivatives	17	[1]	27	[2]
Georgia Power [Member] | Energy Related Derivative [Member] | Gross Amount Of Derivatives [Member]
Derivative [Line Items]
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	(3)	[3]	(7)	[4]
Derivative Liability, Fair Value, Amount Not Offset Against Collateral	(3)	[3]	(7)	[4]
Georgia Power [Member] | Interest Rate Contract [Member]
Derivative [Line Items]
Derivative Asset, Fair Value, Amount Offset Against Collateral	2		0
Derivative Liability, Fair Value, Amount Offset Against Collateral	1		8
Georgia Power [Member] | Interest Rate Contract [Member] | Net Amount Of Derivatives [Member]
Derivative [Line Items]
Energy-related derivatives	5	[1]	6	[2]
Energy-related derivatives	4	[1]	14	[2]
Georgia Power [Member] | Interest Rate Contract [Member] | Gross Amount Of Derivatives [Member]
Derivative [Line Items]
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	(3)	[3]	(6)	[4]
Derivative Liability, Fair Value, Amount Not Offset Against Collateral	(3)	[3]	(6)	[4]
Gulf Power [Member]
Derivative [Line Items]
Energy-related derivatives	0		0
Energy-related derivatives	74		72
Gulf Power [Member] | Energy Related Derivative [Member]
Derivative [Line Items]
Derivative Asset, Fair Value, Amount Offset Against Collateral	0		0
Derivative Liability, Fair Value, Amount Offset Against Collateral	74		72
Gulf Power [Member] | Energy Related Derivative [Member] | Net Amount Of Derivatives [Member]
Derivative [Line Items]
Energy-related derivatives	0	[1]	0	[2]
Energy-related derivatives	74	[1]	72	[2]
Gulf Power [Member] | Energy Related Derivative [Member] | Gross Amount Of Derivatives [Member]
Derivative [Line Items]
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	0	[3]	0	[4]
Derivative Liability, Fair Value, Amount Not Offset Against Collateral	0	[3]	0	[4]
Gulf Power [Member] | Interest Rate Contract [Member]
Derivative [Line Items]
Derivative Asset, Fair Value, Amount Offset Against Collateral	0		0
Derivative Liability, Fair Value, Amount Offset Against Collateral	0		0
Gulf Power [Member] | Interest Rate Contract [Member] | Net Amount Of Derivatives [Member]
Derivative [Line Items]
Energy-related derivatives	0	[1]	0	[2]
Energy-related derivatives	0	[1]	0	[2]
Gulf Power [Member] | Interest Rate Contract [Member] | Gross Amount Of Derivatives [Member]
Derivative [Line Items]
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	0	[3]	0	[4]
Derivative Liability, Fair Value, Amount Not Offset Against Collateral	0	[3]	0	[4]
Mississippi Power [Member]
Derivative [Line Items]
Energy-related derivatives	0		0
Energy-related derivatives	41		45
Mississippi Power [Member] | Energy Related Derivative [Member]
Derivative [Line Items]
Derivative Asset, Fair Value, Amount Offset Against Collateral	0		0
Derivative Liability, Fair Value, Amount Offset Against Collateral	41		45
Mississippi Power [Member] | Energy Related Derivative [Member] | Net Amount Of Derivatives [Member]
Derivative [Line Items]
Energy-related derivatives	0	[1]	0	[2]
Energy-related derivatives	41	[1]	45	[2]
Mississippi Power [Member] | Energy Related Derivative [Member] | Gross Amount Of Derivatives [Member]
Derivative [Line Items]
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	0	[3]	0	[4]
Derivative Liability, Fair Value, Amount Not Offset Against Collateral	0	[3]	0	[4]
Mississippi Power [Member] | Interest Rate Contract [Member]
Derivative [Line Items]
Derivative Asset, Fair Value, Amount Offset Against Collateral	0		0
Derivative Liability, Fair Value, Amount Offset Against Collateral	0		0
Mississippi Power [Member] | Interest Rate Contract [Member] | Net Amount Of Derivatives [Member]
Derivative [Line Items]
Energy-related derivatives	0	[1]	0	[2]
Energy-related derivatives	0	[1]	0	[2]
Mississippi Power [Member] | Interest Rate Contract [Member] | Gross Amount Of Derivatives [Member]
Derivative [Line Items]
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	0	[3]	0	[4]
Derivative Liability, Fair Value, Amount Not Offset Against Collateral	0	[3]	0	[4]
Southern Power [Member]
Derivative [Line Items]
Energy-related derivatives	0		5
Energy-related derivatives	0		4
Southern Power [Member] | Energy Related Derivative [Member]
Derivative [Line Items]
Derivative Asset, Fair Value, Amount Offset Against Collateral	0		5
Derivative Liability, Fair Value, Amount Offset Against Collateral	0		4
Southern Power [Member] | Energy Related Derivative [Member] | Net Amount Of Derivatives [Member]
Derivative [Line Items]
Energy-related derivatives	0	[1]	5	[2]
Energy-related derivatives	0	[1]	4	[2]
Southern Power [Member] | Energy Related Derivative [Member] | Gross Amount Of Derivatives [Member]
Derivative [Line Items]
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	0	[3]	0	[4]
Derivative Liability, Fair Value, Amount Not Offset Against Collateral	0	[3]	0	[4]
Southern Power [Member] | Interest Rate Contract [Member]
Derivative [Line Items]
Derivative Asset, Fair Value, Amount Offset Against Collateral	0		0
Derivative Liability, Fair Value, Amount Offset Against Collateral	0		0
Southern Power [Member] | Interest Rate Contract [Member] | Net Amount Of Derivatives [Member]
Derivative [Line Items]
Energy-related derivatives	0	[1]	0	[2]
Energy-related derivatives	0	[1]	0	[2]
Southern Power [Member] | Interest Rate Contract [Member] | Gross Amount Of Derivatives [Member]
Derivative [Line Items]
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	0	[3]	0	[4]
Derivative Liability, Fair Value, Amount Not Offset Against Collateral	$ 0	[3]	$ 0	[4]
[1]	None of the registrants offsets fair value amounts for multiple derivative instruments executed with the same counterparty on the balance sheets; therefore, gross and net amounts of derivative assets and liabilities presented on the balance sheets are the same.
[2]	None of the registrants offsets fair value amounts for multiple derivative instruments executed with the same counterparty on the balance sheets; therefore, gross and net amounts of derivative assets and liabilities presented on the balance sheets are the same.
[3]	Includes gross amounts subject to netting terms that are not offset on the balance sheets and any cash/financial collateral pledged or received.
[4]	Includes gross amounts subject to netting terms that are not offset on the balance sheets and any cash/financial collateral pledged or received.

Derivatives - Pre-tax Effects o

Derivatives - Pre-tax Effects of Derivatives Designated as Cash Flow Hedging Instruments (Details) - USD ($) $ in Millions	3 Months Ended
	Jun. 30, 2015		Jun. 30, 2014	Dec. 31, 2014
Southern Company [Member] | Energy Related Derivative [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Regulatory Hedge Unrealized Gain (Loss) Recognized on the Balance Sheet	$ (175)			$ (190)
Southern Company [Member] | Energy Related Derivative [Member] | Other regulatory assets current [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Regulatory Hedge Unrealized Gain (Loss) Recognized on the Balance Sheet	(99)			(118)
Southern Company [Member] | Energy Related Derivative [Member] | Other regulatory assets deferred [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Regulatory Hedge Unrealized Gain (Loss) Recognized on the Balance Sheet	(81)			(79)
Southern Company [Member] | Energy Related Derivative [Member] | Other regulatory liabilities current [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Regulatory Hedge Unrealized Gain (Loss) Recognized on the Balance Sheet	5	[1]		7	[2]
Southern Company [Member] | Energy Related Derivative [Member] | Other regulatory liabilities deferred [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Regulatory Hedge Unrealized Gain (Loss) Recognized on the Balance Sheet	0	[3]		0	[4]
Southern Company [Member] | Interest Rate Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in OCI on Derivative (Effective Portion)	31		$ 0
Southern Company [Member] | Interest Rate Contract [Member] | Interest Expense [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion)	(2)		(2)
Alabama Power [Member] | Energy Related Derivative [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Regulatory Hedge Unrealized Gain (Loss) Recognized on the Balance Sheet	(46)			(52)
Alabama Power [Member] | Energy Related Derivative [Member] | Other regulatory assets current [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Regulatory Hedge Unrealized Gain (Loss) Recognized on the Balance Sheet	(31)			(32)
Alabama Power [Member] | Energy Related Derivative [Member] | Other regulatory assets deferred [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Regulatory Hedge Unrealized Gain (Loss) Recognized on the Balance Sheet	(17)			(21)
Alabama Power [Member] | Energy Related Derivative [Member] | Other regulatory liabilities current [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Regulatory Hedge Unrealized Gain (Loss) Recognized on the Balance Sheet	2	[1]		1	[2]
Alabama Power [Member] | Energy Related Derivative [Member] | Other regulatory liabilities deferred [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Regulatory Hedge Unrealized Gain (Loss) Recognized on the Balance Sheet	0	[3]		0	[4]
Alabama Power [Member] | Interest Rate Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in OCI on Derivative (Effective Portion)	7		0
Alabama Power [Member] | Interest Rate Contract [Member] | Interest Expense [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion)	(1)		0
Georgia Power [Member] | Energy Related Derivative [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Regulatory Hedge Unrealized Gain (Loss) Recognized on the Balance Sheet	(14)			(20)
Georgia Power [Member] | Energy Related Derivative [Member] | Other regulatory assets current [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Regulatory Hedge Unrealized Gain (Loss) Recognized on the Balance Sheet	(15)			(23)
Georgia Power [Member] | Energy Related Derivative [Member] | Other regulatory assets deferred [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Regulatory Hedge Unrealized Gain (Loss) Recognized on the Balance Sheet	(2)			(4)
Georgia Power [Member] | Energy Related Derivative [Member] | Other regulatory liabilities current [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Regulatory Hedge Unrealized Gain (Loss) Recognized on the Balance Sheet	3	[1]		6	[2]
Georgia Power [Member] | Energy Related Derivative [Member] | Other regulatory liabilities deferred [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Regulatory Hedge Unrealized Gain (Loss) Recognized on the Balance Sheet	0	[3]		1	[4]
Georgia Power [Member] | Interest Rate Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in OCI on Derivative (Effective Portion)	24		0
Georgia Power [Member] | Interest Rate Contract [Member] | Interest Expense [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion)	(1)		0
Gulf Power [Member] | Energy Related Derivative [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Regulatory Hedge Unrealized Gain (Loss) Recognized on the Balance Sheet	(74)			(72)
Gulf Power [Member] | Energy Related Derivative [Member] | Other regulatory assets current [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Regulatory Hedge Unrealized Gain (Loss) Recognized on the Balance Sheet	(32)			(37)
Gulf Power [Member] | Energy Related Derivative [Member] | Other regulatory assets deferred [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Regulatory Hedge Unrealized Gain (Loss) Recognized on the Balance Sheet	(42)			(35)
Gulf Power [Member] | Energy Related Derivative [Member] | Other regulatory liabilities current [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Regulatory Hedge Unrealized Gain (Loss) Recognized on the Balance Sheet	0	[1]		0	[2]
Gulf Power [Member] | Energy Related Derivative [Member] | Other regulatory liabilities deferred [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Regulatory Hedge Unrealized Gain (Loss) Recognized on the Balance Sheet	0	[3]		0	[4]
Mississippi Power [Member] | Energy Related Derivative [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Regulatory Hedge Unrealized Gain (Loss) Recognized on the Balance Sheet	(41)			(45)
Mississippi Power [Member] | Energy Related Derivative [Member] | Other regulatory assets current [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Regulatory Hedge Unrealized Gain (Loss) Recognized on the Balance Sheet	(21)			(26)
Mississippi Power [Member] | Energy Related Derivative [Member] | Other regulatory assets deferred [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Regulatory Hedge Unrealized Gain (Loss) Recognized on the Balance Sheet	(20)			(19)
Mississippi Power [Member] | Energy Related Derivative [Member] | Other regulatory liabilities current [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Regulatory Hedge Unrealized Gain (Loss) Recognized on the Balance Sheet	0	[1]		0	[2]
Mississippi Power [Member] | Energy Related Derivative [Member] | Other regulatory liabilities deferred [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Regulatory Hedge Unrealized Gain (Loss) Recognized on the Balance Sheet	0	[3]		$ 0	[4]
Mississippi Power [Member] | Interest Rate Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in OCI on Derivative (Effective Portion)	0		0
Mississippi Power [Member] | Interest Rate Contract [Member] | Interest Expense [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion)			(1)
Southern Power [Member] | Interest Rate Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in OCI on Derivative (Effective Portion)	0		0
Southern Power [Member] | Interest Rate Contract [Member] | Interest Expense [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion)	$ 0		$ (1)
[1]	Southern Company, Alabama Power, and Georgia Power include other regulatory liabilities, current in other current liabilities.
[2]	Southern Company, Alabama Power, and Georgia Power include other regulatory liabilities, current in other current liabilities.
[3]	Georgia Power includes other regulatory liabilities, deferred in other deferred credits and liabilities.Regulatory Hedge Unrealized Gain (Loss) Recognized on the Balance Sheet at December 31, 2014Derivative Category and Balance SheetLocation SouthernCompany AlabamaPower GeorgiaPower GulfPower MississippiPower (in millions)Energy-related derivatives: Other regulatory assets, current $(118) $(32) $(23) $(37) $(26)Other regulatory assets, deferred (79) (21) (4) (35) (19)Other regulatory liabilities, current (a) 7 1 6 — —Other regulatory liabilities, deferred (b) — — 1 — —Total energy-related derivative gains (losses) $(190) $(52) $(20) $(72) $(45)
[4]	Georgia Power includes other regulatory liabilities, deferred in other deferred credits and liabilities.

Derivatives - Narrative (Detail

Derivatives - Narrative (Details) - Jun. 30, 2015 BTU in Millions, $ in Millions	USD ($)BTU
Derivatives (Textual) [Abstract]
Maximum Potential Collateral Requirements Arising from Credit Risk Related Contingent Features	$ 49
Southern Company [Member]
Derivatives (Textual) [Abstract]
Expected volume of natural gas subject to option to sell back excess gas due to operational constraints | BTU	5
Alabama Power [Member]
Derivatives (Textual) [Abstract]
Expected volume of natural gas subject to option to sell back excess gas due to operational constraints | BTU	1
Maximum Potential Collateral Requirements Arising from Credit Risk Related Contingent Features	$ 49
Georgia Power [Member]
Derivatives (Textual) [Abstract]
Expected volume of natural gas subject to option to sell back excess gas due to operational constraints | BTU	3
Maximum Potential Collateral Requirements Arising from Credit Risk Related Contingent Features	$ 49
Southern Power [Member]
Derivatives (Textual) [Abstract]
Expected volume of natural gas subject to option to sell back excess gas due to operational constraints | BTU	1
Maximum Potential Collateral Requirements Arising from Credit Risk Related Contingent Features	$ 49
Gulf Power [Member]
Derivatives (Textual) [Abstract]
Maximum Potential Collateral Requirements Arising from Credit Risk Related Contingent Features	49
Mississippi Power [Member]
Derivatives (Textual) [Abstract]
Maximum Potential Collateral Requirements Arising from Credit Risk Related Contingent Features	$ 49

Acquisitions - Schedule of Cons

Acquisitions - Schedule of Construction Projects (Details) - Jun. 30, 2015 - Southern Power [Member] $ in Millions		USD ($)MW
Business Acquisition [Line Items]
Nameplate Capacity (in mw) | MW		146
PPA Contract Period		25 years
Minimum [Member]
Business Acquisition [Line Items]
Estimated Construction Cost		$ 260
Maximum [Member]
Business Acquisition [Line Items]
Estimated Construction Cost		$ 280
Decatur Parkway Solar Project, LLC [Member]
Business Acquisition [Line Items]
Nameplate Capacity (in mw) | MW		84
PPA Contract Period		25 years
Decatur Parkway Solar Project, LLC [Member] | Minimum [Member]
Business Acquisition [Line Items]
Estimated Construction Cost	[1]	$ 170
Decatur Parkway Solar Project, LLC [Member] | Maximum [Member]
Business Acquisition [Line Items]
Estimated Construction Cost	[1]	$ 173
Decatur County Solar Project, LLC [Member]
Business Acquisition [Line Items]
Nameplate Capacity (in mw) | MW		20
PPA Contract Period		20 years
Decatur County Solar Project, LLC [Member] | Minimum [Member]
Business Acquisition [Line Items]
Estimated Construction Cost	[1]	$ 45
Decatur County Solar Project, LLC [Member] | Maximum [Member]
Business Acquisition [Line Items]
Estimated Construction Cost	[1]	$ 47
Butler Solar LLC [Member]
Business Acquisition [Line Items]
Nameplate Capacity (in mw) | MW		103
PPA Contract Period		30 years
Butler Solar LLC [Member] | Minimum [Member]
Business Acquisition [Line Items]
Estimated Construction Cost	[1]	$ 220
Butler Solar LLC [Member] | Maximum [Member]
Business Acquisition [Line Items]
Estimated Construction Cost	[1]	$ 230
LS Pawpaw, LLC [Member]
Business Acquisition [Line Items]
Nameplate Capacity (in mw) | MW		30
PPA Contract Period		30 years
LS Pawpaw, LLC [Member] | Minimum [Member]
Business Acquisition [Line Items]
Estimated Construction Cost	[1]	$ 70
LS Pawpaw, LLC [Member] | Maximum [Member]
Business Acquisition [Line Items]
Estimated Construction Cost	[1]	$ 80
Butler Solar Farm, LLC [Member]
Business Acquisition [Line Items]
Nameplate Capacity (in mw) | MW		20
PPA Contract Period		20 years
Butler Solar Farm, LLC [Member] | Minimum [Member]
Business Acquisition [Line Items]
Estimated Construction Cost	[1]	$ 42
Butler Solar Farm, LLC [Member] | Maximum [Member]
Business Acquisition [Line Items]
Estimated Construction Cost	[1]	$ 48
[1]	Includes the acquisition price of all outstanding membership interests.

Acquisitions - Narrative (Detai

Acquisitions - Narrative (Details) $ in Millions	Apr. 30, 2015USD ($)MW	Apr. 15, 2015USD ($)MW	Feb. 24, 2015USD ($)MW	Jun. 30, 2015USD ($)MW
Southern Power [Member]
Business Acquisition [Line Items]
Life Output Of Plant				25 years
Power of solar polycrystalline silicon facility (in MWs) | MW				146
Number of Businesses Acquired				5
Total Cost				$ 188
Southern Power [Member] | SG2 Holdings, LLC [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment				707
Prepaid Long Term Service Agreements				20
Southern Power [Member] | Kay Wind, LLC [Member]
Business Acquisition [Line Items]
Payments to Acquire Businesses, Gross			$ 492
Energy From Wind-Powered Generating Facilities (in MWs) | MW			299
Beginning Year Of Output Of Constructed Plant			2,015
Life Output Of Plant			20 years
Southern Power [Member] | Lost Hills Blackwell Holdings, LLC [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment				98
Prepaid Long Term Service Agreements				9
Payments to Acquire Businesses, Gross		$ 74
Beginning Year Of Output Of Constructed Plant		2,015
Life Output Of Plant		29 years
Southern Power [Member] | Lost Hills Blackwell Holdings, LLC [Member] | Class A Membership Interest [Member]
Business Acquisition [Line Items]
Noncontrolling Interest, Ownership Percentage by Parent		100.00%
Percentage Of Entitled Cash Distributions		51.00%
Southern Power [Member] | Lost Hills Solar Facility [Member]
Business Acquisition [Line Items]
Power of solar polycrystalline silicon facility (in MWs) | MW		22
Southern Power [Member] | Blackwell Solar Facility [Member]
Business Acquisition [Line Items]
Power of solar polycrystalline silicon facility (in MWs) | MW		13
Southern Power [Member] | North Star [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment				266
Prepaid Long Term Service Agreements				21
Payments to Acquire Businesses, Gross	$ 211
Life Output Of Plant	20 years
Power of solar polycrystalline silicon facility (in MWs) | MW	61
Purchased Power Agreement Intangible				$ 24
Southern Power [Member] | North Star [Member] | Class A Membership Interest [Member]
Business Acquisition [Line Items]
Noncontrolling Interest, Ownership Percentage by Parent	100.00%
Percentage Of Entitled Cash Distributions	51.00%
First Solar [Member] | Lost Hills Blackwell Holdings, LLC [Member]
Business Acquisition [Line Items]
Payments to Acquire Businesses, Gross		$ 33
First Solar [Member] | Lost Hills Blackwell Holdings, LLC [Member] | Class B Membership Interest [Member]
Business Acquisition [Line Items]
Noncontrolling Interest, Ownership Percentage by Parent		100.00%
Percentage Of Entitled Cash Distributions		49.00%
First Solar [Member] | North Star [Member]
Business Acquisition [Line Items]
Payments to Acquire Businesses, Gross	$ 100
First Solar [Member] | North Star [Member] | Class B Membership Interest [Member]
Business Acquisition [Line Items]
Noncontrolling Interest, Ownership Percentage by Parent	100.00%
Percentage Of Entitled Cash Distributions	49.00%

Segment and Related Informati54

Segment and Related Information - Financial Data for Business Segments (Details) $ in Millions		3 Months Ended			6 Months Ended				12 Months Ended
		Jun. 30, 2015USD ($)state		Jun. 30, 2014USD ($)	Jun. 30, 2015USD ($)state		Jun. 30, 2014USD ($)		Dec. 31, 2014USD ($)	Dec. 31, 2013USD ($)
Segment Reporting Information [Line Items]
Number of States in which Entity Operates | state		4			4
Operating revenues		$ 4,337		$ 4,467	$ 8,520		$ 9,111
Segment net income (loss)	[1]	629	[2]	611	1,138	[3]	962	[3]
Total assets		74,181			74,181				$ 70,923
Kemper Igcc [Member]
Segment Reporting Information [Line Items]
Pre-tax charge to income		23			32		380		868	$ 1,200
After tax charge to income		14			20		235		536	$ 729
Electric Utilities [Member]
Segment Reporting Information [Line Items]
Operating revenues		4,324		4,454	8,496		9,081
Segment net income (loss)	[1]	607	[2]	611	1,117	[3]	963	[3]
Total assets		73,311			73,311				70,063
Traditional Operating Companies [Member] | Electric Utilities [Member]
Segment Reporting Information [Line Items]
Operating revenues		4,077		4,209	8,025		8,587
Segment net income (loss)	[1]	561	[2]	580	1,038	[3]	899	[3]
Total assets		67,362			67,362				64,644
Southern Power [Member]
Segment Reporting Information [Line Items]
Operating revenues		85		68	199		140
Southern Power [Member] | Electric Utilities [Member]
Segment Reporting Information [Line Items]
Operating revenues		337		329	684		680
Segment net income (loss)	[1]	46	[2]	31	79	[3]	64	[3]
Total assets		6,226			6,226				5,550
Eliminations [Member]
Segment Reporting Information [Line Items]
Operating revenues		(30)		(26)	(59)		(50)
Segment net income (loss)	[1]	4	[2]	(2)	0	[3]	(3)	[3]
Total assets		(490)			(490)				(296)
Eliminations [Member] | Electric Utilities [Member]
Segment Reporting Information [Line Items]
Operating revenues		(90)		(84)	(213)		(186)
Segment net income (loss)	[1]	0	[2]	0	0	[3]	0	[3]
Total assets		(277)			(277)				(131)
All Other [Member]
Segment Reporting Information [Line Items]
Operating revenues		43		39	83		80
Segment net income (loss)	[1]	18	[2]	$ 2	21	[3]	$ 2	[3]
Total assets		$ 1,360			$ 1,360				$ 1,156
[1]	After dividends on preferred and preference stock of subsidiaries.
[2]	Segment net income (loss) for the traditional operating companies for the three months ended June 30, 2015 includes a $23 million pre-tax charge ($14 million after tax) for estimated probable losses on the Kemper IGCC. See Note (B) under "Integrated Coal Gasification Combined Cycle – Kemper IGCC Schedule and Cost Estimate" herein for additional information.
[3]	Segment net income (loss) for the traditional operating companies for the six months ended June 30, 2015 and June 30, 2014 includes a $32 million pre-tax charge ($20 million after tax) and a $380 million pre-tax charge ($235 million after tax), respectively, for estimated probable losses on the Kemper IGCC. See Note (B) under "Integrated Coal Gasification Combined Cycle – Kemper IGCC Schedule and Cost Estimate" herein for additional information.

Segment and Related Informati55

Segment and Related Information - Financial Data for Products and Services (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Revenue from External Customer [Line Items]
Electric Utilities' Revenues	$ 4,324	$ 4,454	$ 8,496	$ 9,081
Retail [Member]
Revenue from External Customer [Line Items]
Electric Utilities' Revenues	3,714	3,770	7,256	7,628
Wholesale [Member]
Revenue from External Customer [Line Items]
Electric Utilities' Revenues	448	515	915	1,119
Other [Member]
Revenue from External Customer [Line Items]
Electric Utilities' Revenues	$ 162	$ 169	$ 325	$ 334