Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Millions	Jun. 30, 2021	Dec. 31, 2020
Current Assets:
Cash and cash equivalents	$ 1,582	$ 1,065
Receivables —
Customer accounts	1,683	1,753
Energy marketing	0	516
Unbilled revenues	643	672
Other accounts and notes	488	512
Accumulated provision for uncollectible accounts	(88)	(118)
Materials and supplies	1,469	1,478
Fossil fuel for generation	475	550
Natural gas for sale	178	460
Prepaid expenses	538	276
Assets from risk management activities, net of collateral	175	147
Regulatory assets – asset retirement obligations	224	214
Natural gas cost under recovery	485	0
Assets held for sale	787	60
Other regulatory assets	728	810
Other current assets	184	222
Total current assets	9,551	8,617
Property, Plant, and Equipment:
In service	112,783	110,516
Less: Accumulated depreciation	33,240	32,397
Plant in service, net of depreciation	79,543	78,119
Nuclear fuel, at amortized cost	816	818
Construction work in progress	9,264	8,697
Total property, plant, and equipment	89,623	87,634
Other Property and Investments:
Goodwill	5,280	5,280
Nuclear decommissioning trusts, at fair value	2,457	2,303
Equity investments in unconsolidated subsidiaries	1,287	1,362
Other intangible assets, net of amortization	466	487
Leveraged leases	569	556
Miscellaneous property and investments	494	398
Total other property and investments	10,553	10,386
Deferred Charges and Other Assets:
Operating lease right-of-use assets, net of amortization	1,775	1,802
Deferred charges related to income taxes	806	796
Unamortized loss on reacquired debt	269	280
Regulatory assets – asset retirement obligations, deferred	4,931	4,934
Other regulatory assets, deferred	7,092	7,198
Other deferred charges and assets	1,307	1,288
Total deferred charges and other assets	16,180	16,298
Total Assets	125,907	122,935
Current Liabilities:
Securities due within one year	2,829	3,507
Notes payable	1,402	609
Energy marketing trade payables	0	494
Accounts payable —
Accounts payable	2,075	2,312
Customer deposits	467	487
Accrued taxes —
Accrued income taxes	40	130
Other accrued taxes	589	699
Accrued interest	510	513
Accrued compensation	770	1,025
Asset retirement obligations	684	585
Liabilities held for sale	677	0
Operating lease obligations	245	241
Other regulatory liabilities	416	509
Other current liabilities	956	968
Total current liabilities	11,660	12,079
Long-term Debt	47,828	45,073
Deferred Credits and Other Liabilities:
Accumulated deferred income taxes	8,710	8,175
Deferred credits related to income taxes	5,593	5,767
Accumulated deferred ITCs	2,247	2,235
Employee benefit obligations	2,004	2,213
Operating lease obligations, deferred	1,604	1,611
Asset retirement obligations, deferred	9,983	10,099
Accrued environmental remediation	208	216
Other cost of removal obligations	2,190	2,211
Other regulatory liabilities, deferred	256	251
Other deferred credits and liabilities	587	480
Total deferred credits and other liabilities	33,382	33,258
Total Liabilities	92,870	90,410
Redeemable Preferred Stock of Subsidiaries	291	291
Common Stockholder's Equity (See accompanying statements)	32,746	32,234
Total Liabilities and Stockholders' Equity	125,907	122,935
ALABAMA POWER CO
Current Assets:
Cash and cash equivalents	727	530
Receivables —
Customer accounts	402	429
Unbilled revenues	180	152
Affiliated	40	31
Other accounts and notes	80	66
Accumulated provision for uncollectible accounts	(25)	(43)
Materials and supplies	550	546
Fossil fuel for generation	214	235
Prepaid expenses	94	42
Other regulatory assets	221	226
Other current assets	88	33
Total current assets	2,571	2,247
Property, Plant, and Equipment:
In service	32,390	31,816
Less: Accumulated depreciation	10,229	10,009
Plant in service, net of depreciation	22,161	21,807
Nuclear fuel, at amortized cost	254	270
Construction work in progress	978	866
Total property, plant, and equipment	23,393	22,943
Other Property and Investments:
Nuclear decommissioning trusts, at fair value	1,251	1,157
Equity investments in unconsolidated subsidiaries	64	63
Miscellaneous property and investments	127	131
Total other property and investments	1,442	1,351
Deferred Charges and Other Assets:
Operating lease right-of-use assets, net of amortization	130	151
Deferred charges related to income taxes	237	235
Regulatory assets – asset retirement obligations, deferred	1,437	1,441
Other regulatory assets, deferred	2,168	2,162
Other deferred charges and assets	313	273
Total deferred charges and other assets	4,285	4,262
Total Assets	31,691	30,803
Current Liabilities:
Securities due within one year	616	311
Accounts payable —
Affiliated	290	316
Other	378	545
Customer deposits	106	104
Accrued taxes —
Accrued taxes	173	152
Accrued interest	93	90
Accrued compensation	176	212
Asset retirement obligations	296	254
Other regulatory liabilities	37	108
Other current liabilities	119	107
Total current liabilities	2,284	2,199
Long-term Debt	8,649	8,558
Deferred Credits and Other Liabilities:
Accumulated deferred income taxes	3,390	3,273
Deferred credits related to income taxes	1,988	2,016
Accumulated deferred ITCs	91	94
Employee benefit obligations	173	214
Operating lease obligations, deferred	100	119
Asset retirement obligations, deferred	3,651	3,720
Other cost of removal obligations	291	335
Other regulatory liabilities, deferred	93	124
Other deferred credits and liabilities	53	50
Total deferred credits and other liabilities	9,830	9,945
Total Liabilities	20,763	20,702
Redeemable Preferred Stock	291	291
Common Stockholder's Equity (See accompanying statements)	10,637	9,810
Total Liabilities and Stockholders' Equity	31,691	30,803
GEORGIA POWER CO
Current Assets:
Cash and cash equivalents	49	9
Receivables —
Customer accounts	601	621
Unbilled revenues	334	233
Joint owner accounts	98	123
Affiliated	27	21
Other accounts and notes	40	67
Accumulated provision for uncollectible accounts	(3)	(26)
Materials and supplies	631	592
Fossil fuel for generation	223	278
Regulatory assets – storm damage	150	213
Regulatory assets – asset retirement obligations	183	166
Other regulatory assets	240	248
Other current assets	140	143
Total current assets	2,713	2,688
Property, Plant, and Equipment:
In service	40,408	39,682
Less: Accumulated depreciation	12,540	12,251
Plant in service, net of depreciation	27,868	27,431
Nuclear fuel, at amortized cost	562	548
Construction work in progress	7,062	6,857
Total property, plant, and equipment	35,492	34,836
Other Property and Investments:
Nuclear decommissioning trusts, at fair value	1,207	1,145
Equity investments in unconsolidated subsidiaries	51	51
Miscellaneous property and investments	66	63
Total other property and investments	1,324	1,259
Deferred Charges and Other Assets:
Operating lease right-of-use assets, net of amortization	1,236	1,308
Deferred charges related to income taxes	535	527
Regulatory assets – asset retirement obligations, deferred	3,281	3,291
Other regulatory assets, deferred	2,550	2,692
Other deferred charges and assets	494	479
Total deferred charges and other assets	8,096	8,297
Total Assets	47,625	47,080
Current Liabilities:
Securities due within one year	627	542
Notes payable	310	60
Accounts payable —
Affiliated	587	597
Other	755	753
Customer deposits	268	276
Accrued taxes —
Accrued taxes	322	407
Accrued interest	138	130
Accrued compensation	164	233
Asset retirement obligations	321	287
Operating lease obligations	152	151
Other regulatory liabilities	277	228
Over recovered fuel clause revenues	0	113
Other current liabilities	230	254
Total current liabilities	4,151	4,031
Long-term Debt	13,023	12,428
Deferred Credits and Other Liabilities:
Accumulated deferred income taxes	3,138	3,272
Deferred credits related to income taxes	2,463	2,588
Accumulated deferred ITCs	322	273
Employee benefit obligations	518	586
Operating lease obligations, deferred	1,111	1,156
Asset retirement obligations, deferred	5,962	5,978
Other deferred credits and liabilities	391	267
Total deferred credits and other liabilities	13,905	14,120
Total Liabilities	31,079	30,579
Common Stockholder's Equity (See accompanying statements)	16,546	16,501
Total Liabilities and Stockholders' Equity	47,625	47,080
MISSISSIPPI POWER CO
Current Assets:
Cash and cash equivalents	478	39
Receivables —
Customer accounts	38	34
Unbilled revenues	42	38
Affiliated	26	32
Other accounts and notes	30	32
Materials and supplies	68	65
Fossil fuel for generation	25	24
Other regulatory assets	53	60
Other current assets	41	20
Total current assets	801	344
Property, Plant, and Equipment:
In service	5,053	5,011
Less: Accumulated depreciation	1,556	1,545
Plant in service, net of depreciation	3,497	3,466
Construction work in progress	126	146
Total property, plant, and equipment	3,623	3,612
Other Property and Investments:
Total other property and investments	180	151
Deferred Charges and Other Assets:
Deferred charges related to income taxes	31	32
Regulatory assets – asset retirement obligations, deferred	213	201
Other regulatory assets, deferred	375	388
Accumulated deferred income taxes	123	129
Other deferred charges and assets	66	55
Total deferred charges and other assets	808	805
Total Assets	5,412	4,912
Current Liabilities:
Securities due within one year	421	406
Notes payable	0	25
Accounts payable —
Affiliated	71	63
Other	66	109
Accrued taxes —
Accrued taxes	63	114
Accrued interest	15	15
Accrued compensation	24	34
Asset retirement obligations	36	27
Other regulatory liabilities	62	49
Over recovered fuel clause revenues	12	34
Other current liabilities	51	40
Total current liabilities	821	916
Long-term Debt	1,512	1,013
Deferred Credits and Other Liabilities:
Accumulated deferred income taxes	460	447
Deferred credits related to income taxes	283	287
Employee benefit obligations	102	113
Asset retirement obligations, deferred	135	150
Other cost of removal obligations	193	194
Other regulatory liabilities, deferred	26	15
Other deferred credits and liabilities	31	35
Total deferred credits and other liabilities	1,230	1,241
Total Liabilities	3,563	3,170
Common Stockholder's Equity (See accompanying statements)	1,849	1,742
Total Liabilities and Stockholders' Equity	5,412	4,912
SOUTHERN POWER CO
Current Assets:
Cash and cash equivalents	165	182
Receivables —
Customer accounts	168	125
Affiliated	52	37
Other accounts and notes	48	27
Materials and supplies	101	157
Prepaid income taxes	153	11
Other current assets	56	36
Total current assets	743	575
Property, Plant, and Equipment:
In service	14,372	13,904
Less: Accumulated depreciation	2,991	2,842
Plant in service, net of depreciation	11,381	11,062
Construction work in progress	250	127
Total property, plant, and equipment	11,631	11,189
Other Property and Investments:
Intangible assets, net of amortization	292	302
Equity investments in unconsolidated subsidiaries	84	19
Miscellaneous property and investments	84	19
Total other property and investments	376	321
Deferred Charges and Other Assets:
Operating lease right-of-use assets, net of amortization	476	415
Prepaid LTSAs	179	155
Accumulated deferred income taxes	0	262
Income taxes receivable, non-current	31	25
Other deferred charges and assets	272	293
Total deferred charges and other assets	958	1,150
Total Assets	13,708	13,235
Current Liabilities:
Securities due within one year	1,012	299
Notes payable	119	175
Accounts payable —
Affiliated	75	65
Other	90	92
Accrued taxes —
Accrued income taxes	7	8
Other accrued taxes	20	22
Accrued interest	24	32
Other current liabilities	116	132
Total current liabilities	1,463	825
Long-term Debt	3,036	3,393
Deferred Credits and Other Liabilities:
Accumulated deferred income taxes	221	123
Accumulated deferred ITCs	1,643	1,672
Operating lease obligations, deferred	488	426
Other deferred credits and liabilities	167	165
Total deferred credits and other liabilities	2,519	2,386
Total Liabilities	7,018	6,604
Common Stockholder's Equity (See accompanying statements)	6,690	6,631
Total Liabilities and Stockholders' Equity	13,708	13,235
SOUTHERN Co GAS
Current Assets:
Cash and cash equivalents	37	17
Receivables —
Customer accounts	283	353
Energy marketing	0	516
Unbilled revenues	74	219
Affiliated	3	4
Other accounts and notes	31	51
Accumulated provision for uncollectible accounts	(45)	(40)
Natural gas for sale	178	460
Prepaid expenses	162	48
Assets from risk management activities, net of collateral	22	118
Natural gas cost under recovery	485	0
Assets held for sale	736	0
Other regulatory assets	97	102
Other current assets	40	38
Total current assets	2,103	1,886
Property, Plant, and Equipment:
In service	18,051	17,611
Less: Accumulated depreciation	4,942	4,821
Plant in service, net of depreciation	13,109	12,790
Construction work in progress	790	648
Total property, plant, and equipment	13,899	13,438
Other Property and Investments:
Goodwill	5,015	5,015
Equity investments in unconsolidated subsidiaries	1,189	1,290
Other intangible assets, net of amortization	44	51
Miscellaneous property and investments	19	19
Total other property and investments	6,267	6,375
Deferred Charges and Other Assets:
Operating lease right-of-use assets, net of amortization	72	81
Other regulatory assets, deferred	697	615
Other deferred charges and assets	197	235
Total deferred charges and other assets	966	931
Total Assets	23,235	22,630
Current Liabilities:
Securities due within one year	48	333
Notes payable	834	324
Energy marketing trade payables	0	494
Accounts payable —
Affiliated	50	56
Other	311	373
Customer deposits	75	90
Accrued taxes —
Accrued taxes	79	83
Accrued interest	55	58
Accrued compensation	105	106
Liabilities held for sale	677	0
Other regulatory liabilities	39	122
Temporary LIFO liquidation	182	0
Other current liabilities	125	150
Total current liabilities	2,580	2,189
Long-term Debt	6,234	6,293
Deferred Credits and Other Liabilities:
Accumulated deferred income taxes	1,413	1,265
Deferred credits related to income taxes	831	847
Employee benefit obligations	267	283
Operating lease obligations, deferred	59	67
Accrued environmental remediation	208	216
Other cost of removal obligations	1,673	1,649
Other deferred credits and liabilities	41	54
Total deferred credits and other liabilities	4,492	4,381
Total Liabilities	13,306	12,863
Common Stockholder's Equity (See accompanying statements)	9,929	9,767
Total Liabilities and Stockholders' Equity	$ 23,235	$ 22,630