Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Millions	Sep. 30, 2017	Dec. 31, 2016
Current Assets:
Cash and cash equivalents	$ 1,841	$ 1,975
Receivables —
Customer accounts receivable	1,744	1,583
Energy marketing receivables	427	623
Unbilled revenues	595	706
Under recovered fuel clause revenues	62	0
Income taxes receivable, current	138	544
Other accounts and notes receivable	578	377
Accumulated provision for uncollectible accounts	(43)	(43)
Materials and supplies	1,499	1,462
Fossil fuel for generation	571	689
Natural gas for sale	631	631
Prepaid expenses	365	364
Other regulatory assets, current	585	581
Other current assets	209	230
Total current assets	9,202	9,722
Property, Plant, and Equipment:
In service	102,014	98,416
Less: Accumulated depreciation	31,164	29,852
Plant in service, net of depreciation	70,850	68,564
Nuclear fuel, at amortized cost	865	905
Construction work in progress	8,026	8,977
Total property, plant, and equipment	79,741	78,446
Other Property and Investments:
Goodwill	6,267	6,251
Equity investments in unconsolidated subsidiaries	1,637	1,549
Other intangible assets, net of amortization	902	970
Nuclear decommissioning trusts, at fair value	1,783	1,606
Leveraged leases	788	774
Miscellaneous property and investments	236	270
Total other property and investments	11,613	11,420
Deferred Charges and Other Assets:
Deferred charges related to income taxes	1,318	1,629
Unamortized loss on reacquired debt	210	223
Other regulatory assets, deferred	6,718	6,851
Other deferred charges and assets	1,513	1,406
Total deferred charges and other assets	9,759	10,109
Total Assets	110,315	109,697
Current Liabilities:
Securities due within one year	3,505	2,587
Notes payable	2,579	2,241
Energy marketing trade payables	451	597
Accounts payable —
Accounts payable	2,353	2,228
Customer deposits	550	558
Accrued taxes —
Accrued income taxes	176	193
Unrecognized tax benefits	17	385
Other accrued taxes	690	667
Accrued interest	443	518
Accrued compensation	703	915
Asset retirement obligations, current	245	378
Acquisitions payable	0	489
Other regulatory liabilities, current	139	236
Other current liabilities	752	925
Total current liabilities	12,603	12,917
Long-term Debt	44,042	42,629
Deferred Credits and Other Liabilities:
Accumulated deferred income taxes	14,321	14,092
Accumulated deferred ITCs	2,290	2,228
Employee benefit obligations	2,139	2,299
Asset retirement obligations, deferred	4,356	4,136
Other cost of removal obligations	2,708	2,748
Other regulatory liabilities, deferred	449	476
Other deferred credits and liabilities	1,048	1,278
Total deferred credits and other liabilities	27,311	27,257
Total Liabilities	83,956	82,803
Redeemable Preferred Stock of Subsidiaries	361	118
Redeemable Noncontrolling Interests	59	164
Common Stockholders' Equity:
Par value	5,018	4,952
Paid-in capital	10,300	9,661
Treasury, at cost	(35)	(31)
Retained earnings (accumulated deficit)	8,981	10,356
Accumulated other comprehensive income (loss)	(182)	(180)
Total Common Stockholders' Equity	24,082	24,758
Preferred and Preference Stock of Subsidiaries	462	609
Noncontrolling Interests	1,395	1,245
Total Stockholders' Equity	25,939	26,612
Total Liabilities and Stockholders' Equity	110,315	109,697
ALABAMA POWER CO
Current Assets:
Cash and cash equivalents	953	420
Receivables —
Customer accounts receivable	428	348
Unbilled revenues	149	146
Other accounts and notes receivable	47	27
Affiliated	45	40
Accumulated provision for uncollectible accounts	(8)	(10)
Materials and supplies	455	435
Fossil fuel for generation	171	205
Prepaid expenses	58	34
Other regulatory assets, current	122	149
Other current assets	5	11
Total current assets	2,425	1,805
Property, Plant, and Equipment:
In service	26,619	26,031
Less: Accumulated depreciation	9,463	9,112
Plant in service, net of depreciation	17,156	16,919
Nuclear fuel, at amortized cost	314	336
Construction work in progress	928	491
Total property, plant, and equipment	18,398	17,746
Other Property and Investments:
Equity investments in unconsolidated subsidiaries	65	66
Nuclear decommissioning trusts, at fair value	869	792
Miscellaneous property and investments	121	112
Total other property and investments	1,055	970
Deferred Charges and Other Assets:
Deferred charges related to income taxes	525	525
Deferred under recovered regulatory clause revenues	17	150
Other regulatory assets, deferred	1,191	1,157
Other deferred charges and assets	178	163
Total deferred charges and other assets	1,911	1,995
Total Assets	23,789	22,516
Current Liabilities:
Securities due within one year	325	561
Accounts payable —
Affiliated	275	297
Other	376	433
Customer deposits	92	88
Accrued taxes —
Accrued income taxes	115	45
Other accrued taxes	128	42
Accrued interest	75	78
Accrued compensation	151	193
Other regulatory liabilities, current	4	85
Other current liabilities	50	76
Total current liabilities	1,591	1,898
Long-term Debt	7,083	6,535
Deferred Credits and Other Liabilities:
Accumulated deferred income taxes	4,919	4,654
Deferred credits related to income taxes	60	65
Accumulated deferred ITCs	118	110
Employee benefit obligations	289	300
Asset retirement obligations, deferred	1,564	1,503
Other cost of removal obligations	630	684
Other regulatory liabilities, deferred	93	100
Other deferred credits and liabilities	51	63
Total deferred credits and other liabilities	7,724	7,479
Total Liabilities	16,398	15,912
Redeemable Preferred Stock	329	85
Preference Stock	196	196
Common Stockholders' Equity:
Par value	1,222	1,222
Paid-in capital	2,961	2,613
Retained earnings (accumulated deficit)	2,711	2,518
Accumulated other comprehensive income (loss)	(28)	(30)
Total Common Stockholders' Equity	6,866	6,323
Total Liabilities and Stockholders' Equity	23,789	22,516
GEORGIA POWER CO
Current Assets:
Cash and cash equivalents	266	3
Receivables —
Customer accounts receivable	670	523
Unbilled revenues	276	224
Under recovered fuel clause revenues	62	0
Joint owner accounts receivable	222	57
Other accounts and notes receivable	82	81
Affiliated	21	18
Accumulated provision for uncollectible accounts	(3)	(3)
Materials and supplies	480	479
Fossil fuel for generation	300	298
Prepaid expenses	82	105
Other regulatory assets, current	200	193
Other current assets	27	38
Total current assets	2,685	2,016
Property, Plant, and Equipment:
In service	34,589	33,841
Less: Accumulated depreciation	11,655	11,317
Plant in service, net of depreciation	22,934	22,524
Nuclear fuel, at amortized cost	551	569
Construction work in progress	5,751	4,939
Total property, plant, and equipment	29,236	28,032
Other Property and Investments:
Equity investments in unconsolidated subsidiaries	53	60
Nuclear decommissioning trusts, at fair value	914	814
Miscellaneous property and investments	51	46
Total other property and investments	1,018	920
Deferred Charges and Other Assets:
Deferred charges related to income taxes	669	676
Other regulatory assets, deferred	2,890	2,774
Other deferred charges and assets	608	417
Total deferred charges and other assets	4,167	3,867
Total Assets	37,106	34,835
Current Liabilities:
Securities due within one year	261	460
Notes payable	400	391
Accounts payable —
Affiliated	396	438
Other	1,012	589
Customer deposits	270	265
Accrued taxes —
Accrued income taxes	353	407
Accrued interest	121	106
Accrued compensation	164	224
Asset retirement obligations, current	214	299
Other current liabilities	192	297
Total current liabilities	3,383	3,476
Long-term Debt	11,610	10,225
Deferred Credits and Other Liabilities:
Accumulated deferred income taxes	6,328	6,000
Accumulated deferred ITCs	248	256
Employee benefit obligations	665	703
Asset retirement obligations, deferred	2,367	2,233
Other deferred credits and liabilities	232	320
Total deferred credits and other liabilities	9,840	9,512
Total Liabilities	24,833	23,213
Redeemable Preferred Stock	45	45
Preference Stock	221	221
Common Stockholders' Equity:
Par value	398	398
Paid-in capital	7,308	6,885
Retained earnings (accumulated deficit)	4,311	4,086
Accumulated other comprehensive income (loss)	(10)	(13)
Total Common Stockholders' Equity	12,007	11,356
Total Liabilities and Stockholders' Equity	37,106	34,835
GULF POWER CO
Current Assets:
Cash and cash equivalents	37	56
Receivables —
Customer accounts receivable	96	72
Unbilled revenues	68	55
Under recovered fuel clause revenues	15	17
Income taxes receivable, current	15	0
Other accounts and notes receivable	12	6
Affiliated	13	17
Accumulated provision for uncollectible accounts	(1)	(1)
Materials and supplies	58	55
Fossil fuel for generation	64	71
Other regulatory assets, current	55	44
Other current assets	15	30
Total current assets	447	422
Property, Plant, and Equipment:
In service	5,181	5,140
Less: Accumulated depreciation	1,457	1,382
Plant in service, net of depreciation	3,724	3,758
Construction work in progress	75	51
Total property, plant, and equipment	3,799	3,809
Deferred Charges and Other Assets:
Deferred charges related to income taxes	56	58
Other regulatory assets, deferred	499	512
Other deferred charges and assets	22	21
Total deferred charges and other assets	577	591
Total Assets	4,823	4,822
Current Liabilities:
Securities due within one year	7	87
Notes payable	0	268
Accounts payable —
Affiliated	46	59
Other	55	54
Customer deposits	35	35
Accrued taxes —
Other accrued taxes	41	20
Accrued interest	20	8
Accrued compensation	30	40
Deferred capacity expense, current	22	22
Other regulatory liabilities, current	1	16
Other current liabilities	37	40
Total current liabilities	294	649
Long-term Debt	1,285	987
Deferred Credits and Other Liabilities:
Accumulated deferred income taxes	1,003	948
Employee benefit obligations	90	96
Deferred capacity expense	103	119
Asset retirement obligations, deferred	125	120
Other cost of removal obligations	218	249
Other regulatory liabilities, deferred	45	47
Other deferred credits and liabilities	71	71
Total deferred credits and other liabilities	1,655	1,650
Total Liabilities	3,234	3,286
Preference Stock	0	147
Common Stockholders' Equity:
Par value	678	503
Paid-in capital	600	589
Retained earnings (accumulated deficit)	312	296
Accumulated other comprehensive income (loss)	(1)	1
Total Common Stockholders' Equity	1,589	1,389
Total Liabilities and Stockholders' Equity	4,823	4,822
MISSISSIPPI POWER CO
Current Assets:
Cash and cash equivalents	231	224
Receivables —
Customer accounts receivable	38	29
Unbilled revenues	41	42
Income taxes receivable, current	102	544
Other accounts and notes receivable	15	14
Affiliated	15	15
Materials and supplies	45	76
Fossil fuel for generation	20	100
Other regulatory assets, current	113	115
Other current assets	8	8
Total current assets	628	1,167
Property, Plant, and Equipment:
In service	4,836	4,865
Less: Accumulated depreciation	1,312	1,289
Plant in service, net of depreciation	3,524	3,576
Construction work in progress	75	2,545
Total property, plant, and equipment	3,599	6,121
Other Property and Investments:
Total other property and investments	28	12
Deferred Charges and Other Assets:
Deferred charges related to income taxes	62	361
Other regulatory assets, deferred	436	518
Accumulated deferred income taxes	279	0
Other deferred charges and assets	23	56
Total deferred charges and other assets	800	935
Total Assets	5,055	8,235
Current Liabilities:
Securities due within one year - parent	0	551
Securities due within one year	1,028	78
Notes payable	4	23
Accounts payable —
Affiliated	56	62
Other	82	135
Customer deposits	16	16
Accrued taxes —
Unrecognized tax benefits	2	383
Other accrued taxes	78	99
Accrued interest	16	46
Accrued compensation	29	42
Asset retirement obligations, current	15	32
Over recovered fuel clause liabilities	4	51
Other current liabilities	67	20
Total current liabilities	1,397	1,538
Long-term Debt	1,167	2,424
Deferred Credits and Other Liabilities:
Accumulated deferred income taxes	0	756
Employee benefit obligations	109	115
Asset retirement obligations, deferred	150	146
Other cost of removal obligations	175	170
Other regulatory liabilities, deferred	87	84
Other deferred credits and liabilities	23	26
Total deferred credits and other liabilities	544	1,297
Total Liabilities	3,108	5,259
Redeemable Preferred Stock	33	33
Common Stockholders' Equity:
Par value	38	38
Paid-in capital	4,529	3,525
Retained earnings (accumulated deficit)	(2,650)	(616)
Accumulated other comprehensive income (loss)	(3)	(4)
Total Common Stockholders' Equity	1,914	2,943
Total Liabilities and Stockholders' Equity	5,055	8,235
SOUTHERN POWER CO
Current Assets:
Cash and cash equivalents	178	1,099
Receivables —
Customer accounts receivable	148	102
Other accounts and notes receivable	61	34
Affiliated	74	57
Materials and supplies	351	337
Fossil fuel for generation	15	15
Prepaid income taxes	51	74
Other current assets	26	39
Total current assets	904	1,757
Property, Plant, and Equipment:
In service	13,734	12,728
Less: Accumulated depreciation	1,823	1,484
Plant in service, net of depreciation	11,911	11,244
Construction work in progress	425	398
Total property, plant, and equipment	12,336	11,642
Other Property and Investments:
Goodwill	2	2
Intangible assets, net (including goodwill)	417	436
Total other property and investments	417	436
Deferred Charges and Other Assets:
Prepaid LTSAs	77	101
Accumulated deferred income taxes	400	594
Income taxes receivable, non-current	53	11
Other deferred charges and assets — affiliated	6	13
Other deferred charges and assets	455	615
Total deferred charges and other assets	991	1,334
Total Assets	14,648	15,169
Current Liabilities:
Securities due within one year	864	560
Notes payable	120	209
Accounts payable —
Affiliated	93	88
Other	84	278
Accrued taxes —
Accrued income taxes	101	148
Other accrued taxes	30	7
Accrued interest	36	36
Acquisitions payable	0	461
Contingent consideration	15	46
Other current liabilities	58	70
Total current liabilities	1,401	1,903
Long-term Debt	4,946	5,068
Deferred Credits and Other Liabilities:
Accumulated deferred income taxes	191	152
Accumulated deferred ITCs	1,900	1,839
Asset retirement obligations, deferred	76	64
Other deferred credits and liabilities	232	304
Total deferred credits and other liabilities	2,399	2,359
Total Liabilities	8,746	9,330
Redeemable Noncontrolling Interests	59	164
Common Stockholders' Equity:
Par value	0	0
Paid-in capital	3,661	3,671
Retained earnings (accumulated deficit)	762	724
Accumulated other comprehensive income (loss)	25	35
Total Common Stockholders' Equity	4,448	4,430
Noncontrolling interests	1,395	1,245
Total Stockholders' Equity	5,843	5,675
Total Liabilities and Stockholders' Equity	14,648	15,169
SOUTHERN Co GAS
Current Assets:
Cash and cash equivalents	21	19
Receivables —
Customer accounts receivable	221	364
Energy marketing receivables	427	623
Unbilled revenues	61	239
Other accounts and notes receivable	61	76
Accumulated provision for uncollectible accounts	(26)	(27)
Materials and supplies	24	26
Natural gas for sale	631	631
Prepaid expenses	103	80
Assets from risk management activities, net of collateral	103	128
Other regulatory assets, current	96	81
Other current assets	25	10
Total current assets	1,747	2,250
Property, Plant, and Equipment:
In service	15,383	14,508
Less: Accumulated depreciation	4,567	4,439
Plant in service, net of depreciation	10,816	10,069
Construction work in progress	596	496
Total property, plant, and equipment	11,412	10,565
Other Property and Investments:
Goodwill	5,967	5,967
Equity investments in unconsolidated subsidiaries	1,609	1,541
Other intangible assets, net of amortization	300	366
Miscellaneous property and investments	21	21
Total other property and investments	7,897	7,895
Deferred Charges and Other Assets:
Other regulatory assets, deferred	944	973
Other deferred charges and assets	190	170
Total deferred charges and other assets	1,134	1,143
Total Assets	22,190	21,853
Current Liabilities:
Securities due within one year	0	22
Notes payable	934	1,257
Energy marketing trade payables	451	597
Accounts payable —
Accounts payable	368	348
Customer deposits	137	153
Accrued taxes —
Accrued income taxes	0	26
Other accrued taxes	70	68
Accrued interest	66	48
Accrued compensation	46	58
Liabilities from risk management activities, net of collateral	28	62
Other regulatory liabilities, current	126	102
Accrued environmental remediation, current	54	69
Other current liabilities	112	108
Total current liabilities	2,392	2,918
Long-term Debt	5,862	5,259
Deferred Credits and Other Liabilities:
Accumulated deferred income taxes	2,214	1,975
Employee benefit obligations	431	441
Accrued environmental remediation	345	357
Other cost of removal obligations	1,656	1,616
Other regulatory liabilities, deferred	35	51
Other deferred credits and liabilities	88	127
Total deferred credits and other liabilities	4,769	4,567
Total Liabilities	13,023	12,744
Common Stockholders' Equity:
Par value	0	0
Paid-in capital	9,185	9,095
Retained earnings (accumulated deficit)	(41)	(12)
Accumulated other comprehensive income (loss)	23	26
Total Stockholders' Equity	9,167	9,109
Total Liabilities and Stockholders' Equity	$ 22,190	$ 21,853