Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Southern Company [Member]
Operating Activities:
Net income (loss)	$ 2,138	$ 1,731
Adjustments to reconcile net income (loss) to net cash provided from operating activities —
Depreciation and amortization, total	1,787	1,798
Deferred income taxes	821	330
Investment tax credits	319	(70)
Allowance for equity funds used during construction	(163)	(182)
Stock based compensation expense	77	51
Estimated loss on Kemper IGCC	182	798
Income taxes receivable, non-current	(444)	0
Other, net	7	(116)
Changes in certain current assets and liabilities —
-Receivables	(118)	(640)
-Fossil fuel stock	239	522
-Materials and supplies	(22)	(45)
-Other current assets	(18)	(29)
-Accounts payable	(266)	(92)
-Accrued taxes	408	403
-Accrued compensation	(129)	96
-Mirror CWIP	99	112
-Other current liabilities	171	20
Net cash provided from operating activities	5,088	4,687
Investing Activities:
Plant acquisitions	(1,128)	(218)
Property additions	(3,490)	(3,686)
Investment in restricted cash	0	(11)
Nuclear decommissioning trust fund purchases	(1,164)	(635)
Nuclear decommissioning trust fund sales	1,159	633
Cost of removal, net of salvage	(118)	(106)
Change in construction payables	20	11
Prepaid long-term service agreement	(166)	(145)
Other investing activities	7	0
Net cash used for investing activities	(4,880)	(4,157)
Financing Activities:
Increase (decrease) in notes payable, net	662	(1,117)
Proceeds —
Long-term debt issuances	3,992	2,715
Interest-bearing refundable deposit	0	75
Common stock issuances	136	484
Short-term borrowings	280	0
Redemptions and repurchases —
Long-term debt	(2,562)	(437)
Interest-bearing refundable deposits	(275)	0
Preferred and preference stock	(412)	0
Common stock	(115)	(5)
Short-term borrowings	(255)	0
Payment of common stock dividends	(1,465)	(1,391)
Payment of dividends on preferred and preference stock of subsidiaries	(48)	(51)
Other financing activities	253	(48)
Net cash provided from (used for) financing activities	191	225
Net Change in Cash and Cash Equivalents	399	755
Cash and Cash Equivalents at Beginning of Period	710	659
Cash and Cash Equivalents at End of Period	1,109	1,414
Cash paid (received) during the period for --
Interest (net of capitalized amounts)	590	560
Income taxes, net	(13)	263
Noncash transactions - Accrued property additions at end of period	483	415
Alabama Power [Member]
Operating Activities:
Net income (loss)	686	672
Adjustments to reconcile net income (loss) to net cash provided from operating activities —
Depreciation and amortization, total	585	631
Deferred income taxes	85	68
Allowance for equity funds used during construction	(43)	(36)
Other, net	23	(33)
Changes in certain current assets and liabilities —
-Receivables	(160)	(139)
-Fossil fuel stock	69	106
-Materials and supplies	18	(8)
-Other current assets	(28)	(32)
-Accounts payable	(106)	(64)
-Accrued taxes	371	210
-Accrued compensation	(32)	18
-Retail fuel cost over recovery - short-term	81	2
-Other current liabilities	30	3
Net cash provided from operating activities	1,579	1,398
Investing Activities:
Property additions	(938)	(966)
Nuclear decommissioning trust fund purchases	(349)	(178)
Nuclear decommissioning trust fund sales	349	178
Cost of removal, net of salvage	(41)	(50)
Change in construction payables	(48)	39
Other investing activities	(22)	(26)
Net cash used for investing activities	(1,049)	(1,003)
Proceeds —
Senior notes issuances	975	400
Capital contributions from parent company	13	20
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	(27)	(30)
Payment of common stock dividends	(428)	(412)
Other financing activities	(11)	(6)
Net cash provided from (used for) financing activities	(194)	(28)
Net Change in Cash and Cash Equivalents	336	367
Cash and Cash Equivalents at Beginning of Period	273	295
Cash and Cash Equivalents at End of Period	609	662
Cash paid (received) during the period for --
Interest (net of capitalized amounts)	192	174
Income taxes, net	47	227
Noncash transactions - Accrued property additions at end of period	88	57
Georgia Power [Member]
Operating Activities:
Net income (loss)	1,077	1,115
Adjustments to reconcile net income (loss) to net cash provided from operating activities —
Depreciation and amortization, total	766	757
Deferred income taxes	12	121
Allowance for equity funds used during construction	(24)	(29)
Retail fuel cost over recovery — long-term	0	(44)
Deferred expenses	(45)	(35)
Pension, postretirement, and other employee benefits	40	28
Other, net	30	24
Changes in certain current assets and liabilities —
-Receivables	37	(377)
-Fossil fuel stock	141	337
-Prepaid income taxes	244	19
-Other current assets	(17)	(24)
-Accounts payable	(118)	(7)
-Accrued taxes	54	148
-Accrued compensation	(34)	20
-Retail fuel cost over recovery - short-term	0	(14)
-Other current liabilities	(3)	29
Net cash provided from operating activities	2,160	2,068
Investing Activities:
Property additions	(1,321)	(1,364)
Nuclear decommissioning trust fund purchases	(815)	(457)
Nuclear decommissioning trust fund sales	810	455
Cost of removal, net of salvage	(57)	(39)
Change in construction payables, net of joint owner portion	44	16
Prepaid long-term service agreement	(60)	(66)
Other investing activities	11	(3)
Net cash used for investing activities	(1,388)	(1,458)
Financing Activities:
Increase (decrease) in notes payable, net	(26)	(836)
Proceeds —
Capital contributions from parent company	41	39
Pollution control revenue bond	274	40
FFB loan	600	1,000
Short-term borrowings	250	0
Redemptions and repurchases —
Pollution control revenue bond	(268)	(37)
Senior notes	(525)	0
Short-term borrowings	(250)	0
Payment of preferred and preference stock dividends	(13)	(13)
Payment of common stock dividends	(776)	(715)
FFB loan issuance costs	0	(49)
Other financing activities	(18)	(6)
Net cash provided from (used for) financing activities	(711)	(577)
Net Change in Cash and Cash Equivalents	61	33
Cash and Cash Equivalents at Beginning of Period	24	30
Cash and Cash Equivalents at End of Period	85	63
Cash paid (received) during the period for --
Interest (net of capitalized amounts)	251	235
Income taxes, net	311	309
Noncash transactions - Accrued property additions at end of period	192	220
Gulf Power [Member]
Operating Activities:
Net income (loss)	127	124
Adjustments to reconcile net income (loss) to net cash provided from operating activities —
Depreciation and amortization, total	105	115
Deferred income taxes	58	29
Allowance for equity funds used during construction	(11)	(8)
Other, net	16	5
Changes in certain current assets and liabilities —
-Receivables	18	(46)
-Fossil fuel stock	18	44
-Prepaid income taxes	31	9
-Other current assets	1	3
-Accounts payable	(13)	10
-Accrued taxes	46	22
-Accrued compensation	(3)	5
-Over recovered regulatory clause revenues	10	7
-Other current liabilities	8	5
Net cash provided from operating activities	411	324
Investing Activities:
Property additions	(189)	(254)
Cost of removal, net of salvage	(9)	(9)
Change in construction payables	(29)	2
Other investing activities	(6)	(7)
Net cash used for investing activities	(233)	(268)
Financing Activities:
Increase (decrease) in notes payable, net	(34)	(44)
Proceeds —
Senior notes issuances	0	200
Common stock issuances	20	50
Pollution control revenue bond	13	42
Redemptions and repurchases —
Pollution control revenue bond	(13)	(29)
Senior notes	(60)	0
Payment of preferred and preference stock dividends	(7)	(7)
Payment of common stock dividends	(98)	(92)
Other financing activities	3	(1)
Net cash provided from (used for) financing activities	(176)	119
Net Change in Cash and Cash Equivalents	2	175
Cash and Cash Equivalents at Beginning of Period	39	22
Cash and Cash Equivalents at End of Period	41	197
Cash paid (received) during the period for --
Interest (net of capitalized amounts)	27	29
Income taxes, net	(37)	36
Noncash transactions - Accrued property additions at end of period	17	35
Mississippi Power [Member]
Operating Activities:
Net income (loss)	63	(303)
Adjustments to reconcile net income (loss) to net cash provided from operating activities —
Depreciation and amortization, total	94	78
Deferred income taxes	518	159
Investment tax credits	25	(108)
Allowance for equity funds used during construction	(82)	(108)
Regulatory assets associated with Kemper IGCC	(56)	(52)
Estimated loss on Kemper IGCC	182	798
Income taxes receivable, non-current	(544)	0
Other, net	7	10
Changes in certain current assets and liabilities —
-Receivables	7	(48)
-Fossil fuel stock	5	36
-Prepaid income taxes	(1)	(90)
-Other current assets	(8)	(4)
-Accounts payable	(32)	28
-Accrued taxes	24	(17)
-Accrued interest	(6)	24
-Accrued compensation	(8)	8
-Over recovered regulatory clause revenues	59	(18)
-Mirror CWIP	99	112
-Other current liabilities	3	0
Net cash provided from operating activities	349	505
Investing Activities:
Property additions	(626)	(986)
Investment in restricted cash	0	(11)
Change in construction payables	(31)	(40)
Distribution of restricted cash	0	9
Other investing activities	(29)	(22)
Net cash used for investing activities	(686)	(1,050)
Financing Activities:
Increase (decrease) in notes payable, net	475	0
Proceeds —
Capital contributions from parent company	153	311
Bonds — Other	0	23
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 —
Long-term debt to parent company	0	(220)
Other long-term debt	(350)	0
Payment of preferred and preference stock dividends	(1)	(1)
Return of capital	0	(165)
Other financing activities	(7)	(3)
Net cash provided from (used for) financing activities	300	490
Net Change in Cash and Cash Equivalents	(37)	(55)
Cash and Cash Equivalents at Beginning of Period	133	145
Cash and Cash Equivalents at End of Period	96	90
Cash paid (received) during the period for --
Interest (net of capitalized amounts)	6	5
Income taxes, net	(55)	(210)
Noncash transactions - Accrued property additions at end of period	83	124
Noncash transactions - 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)	196	132
Adjustments to reconcile net income (loss) to net cash provided from operating activities —
Depreciation and amortization, total	187	166
Deferred income taxes	222	(6)
Investment tax credits	294	38
Amortization of investment tax credits	(14)	(8)
Deferred revenues	15	(2)
Accrued income taxes, non-current	100	0
Other, net	10	3
Changes in certain current assets and liabilities —
-Receivables	(28)	(63)
-Fossil fuel stock	6	(2)
-Prepaid income taxes	(116)	39
-Other current assets	(5)	(4)
-Accounts payable	1	27
-Accrued taxes	(247)	62
-Other current liabilities	(12)	(11)
Net cash provided from operating activities	609	371
Investing Activities:
Plant acquisitions	(1,128)	(218)
Property additions	(348)	(15)
Change in construction payables	88	(3)
Payments pursuant to long-term service agreements	(65)	(42)
Other investing activities	(1)	(10)
Net cash used for investing activities	(1,454)	(288)
Financing Activities:
Increase (decrease) in notes payable, net	18	20
Proceeds —
Senior notes issuances	650	0
Capital contributions from parent company	226	(4)
Other long-term debt issuances	400	10
Redemptions and repurchases —
Senior notes	(525)	0
Distributions to noncontrolling interests	(6)	0
Contributions from noncontrolling interests	274	7
Payment of common stock dividends	(98)	(98)
Other financing activities	(8)	0
Net cash provided from (used for) financing activities	931	(65)
Net Change in Cash and Cash Equivalents	86	18
Cash and Cash Equivalents at Beginning of Period	75	69
Cash and Cash Equivalents at End of Period	161	87
Cash paid (received) during the period for --
Interest (net of capitalized amounts)	69	78
Income taxes, net	(215)	(91)
Noncash transactions - Accrued property additions at end of period	$ 120	$ 1