Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Operating Activities:
Net income	$ 2,746	$ 4,335
Adjustments to reconcile net income to net cash provided from operating activities —
Depreciation and amortization, total	2,903	2,514
Deferred income taxes	(196)	253
Utilization of federal investment tax credits	319	722
Allowance for equity funds used during construction	(106)	(96)
Impairment charges	0	142
Pension, postretirement, and other employee benefits	(190)	(114)
Settlement of asset retirement obligations	(315)	(225)
Stock based compensation expense	99	87
Estimated loss on Plant Vogtle Units 3 and 4	149	0
Storm damage reserve accruals	171	34
Impairment charges	154	0
(Gain) loss on dispositions, net	(36)	(2,517)
Other, net	93	(20)
Changes in certain current assets and liabilities —
-Receivables	125	588
-Prepayments	(39)	61
-Materials and supplies	(141)	(31)
-Other current assets	(80)	(31)
-Accounts payable	(428)	(1,155)
-Accrued taxes	289	679
-Accrued compensation	(183)	(191)
-Retail fuel cost over recovery	158	31
-Customer refunds	(226)	(30)
-Other current liabilities	(46)	(155)
Net cash provided from operating activities	5,220	4,881
Investing Activities:
Property additions	(5,365)	(5,417)
Nuclear decommissioning trust fund purchases	(714)	(683)
Nuclear decommissioning trust fund sales	708	678
Proceeds from dispositions and asset sales	987	5,036
Cost of removal, net of salvage	(233)	(290)
Change in construction payables, net	(40)	(132)
Investment in unconsolidated subsidiaries	(79)	(141)
Payments pursuant to LTSAs	(139)	(139)
Other investing activities	(17)	15
Net cash used for investing activities	(4,892)	(1,073)
Financing Activities:
Decrease in notes payable, net	(1,534)	(773)
Proceeds —
Long-term debt	7,543	4,737
Common stock	63	623
Short-term borrowings	615	250
Redemptions and repurchases —
Long-term debt	(2,472)	(3,216)
Short-term borrowings	(840)	(1,850)
Distributions to noncontrolling interests	(164)	(125)
Capital contributions from noncontrolling interests	173	11
Purchase of membership interests from noncontrolling interests	(60)	0
Payment of common stock dividends	(2,008)	(1,919)
Other financing activities	(239)	(130)
Net cash provided from (used for) financing activities	1,077	(2,392)
Net Change in Cash, Cash Equivalents, and Restricted Cash	1,405	1,416
Cash, Cash Equivalents, and Restricted Cash at Beginning of Period	1,978	1,519
Cash, Cash Equivalents, and Restricted Cash at End of Period	3,383	2,935
Cash paid during the period for —
Interest, net of amounts capitalized	1,346	1,318
Income taxes, net	66	265
Accrued property additions at end of period	917	953
Right-of-use assets obtained under operating leases	158	76
Right-of-use assets obtained under finance leases	8	31
Interest capitalized	61	55
ALABAMA POWER CO
Operating Activities:
Net income	1,033	993
Adjustments to reconcile net income to net cash provided from operating activities —
Depreciation and amortization, total	731	756
Deferred income taxes	71	148
Allowance for equity funds used during construction	(34)	(41)
Pension, postretirement, and other employee benefits	(71)	(30)
Settlement of asset retirement obligations	(157)	(76)
Other, net	69	18
Changes in certain current assets and liabilities —
-Receivables	(130)	(115)
-Prepayments	(32)	(30)
-Materials and supplies	(55)	11
-Other current assets	(32)	(30)
-Accounts payable	(248)	(267)
-Accrued taxes	142	149
-Accrued compensation	(55)	(55)
-Retail fuel cost over recovery	74	21
-Customer refunds	(64)	(28)
-Other current liabilities	(13)	47
Net cash provided from operating activities	1,229	1,471
Investing Activities:
Property additions	(1,460)	(1,239)
Nuclear decommissioning trust fund purchases	(213)	(201)
Nuclear decommissioning trust fund sales	213	201
Cost of removal, net of salvage	(68)	(79)
Change in construction payables, net	(46)	(99)
Other investing activities	(17)	(22)
Net cash used for investing activities	(1,591)	(1,439)
Proceeds —
Senior notes	600	600
Pollution control revenue bonds	87	0
Capital contributions from parent company	649	1,252
Redemptions and repurchases —
Pollution control revenue bonds	(87)	0
Senior notes	0	(200)
Payment of common stock dividends	(718)	(633)
Other financing activities	(26)	(27)
Net cash provided from (used for) financing activities	505	992
Net Change in Cash, Cash Equivalents, and Restricted Cash	143	1,024
Cash, Cash Equivalents, and Restricted Cash at Beginning of Period	894	313
Cash, Cash Equivalents, and Restricted Cash at End of Period	1,037	1,337
Cash paid during the period for —
Interest, net of amounts capitalized	249	246
Income taxes, net	203	89
Accrued property additions at end of period	154	173
Right-of-use assets obtained under operating leases	63	7
Right-of-use assets obtained under finance leases	2	1
Interest capitalized	11	15
GEORGIA POWER CO
Operating Activities:
Net income	1,411	1,598
Adjustments to reconcile net income to net cash provided from operating activities —
Depreciation and amortization, total	1,206	887
Deferred income taxes	(167)	145
Allowance for equity funds used during construction	(63)	(49)
Pension, postretirement, and other employee benefits	(98)	(85)
Settlement of asset retirement obligations	(130)	(110)
Estimated loss on Plant Vogtle Units 3 and 4	149	0
Storm damage reserve accruals	160	22
Other, net	12	40
Changes in certain current assets and liabilities —
-Receivables	(168)	(128)
-Prepaid income taxes	0	102
-Materials and supplies	(74)	(2)
-Contract assets	(34)	(33)
-Other current assets	(31)	(13)
-Accounts payable	25	(134)
-Accrued taxes	44	138
-Accrued compensation	(36)	(12)
-Retail fuel cost over recovery	84	0
-Customer refunds	(162)	18
-Other current liabilities	(3)	(19)
Net cash provided from operating activities	2,125	2,365
Investing Activities:
Property additions	(2,519)	(2,581)
Nuclear decommissioning trust fund purchases	(500)	(483)
Nuclear decommissioning trust fund sales	495	477
Proceeds from dispositions and asset sales	143	9
Cost of removal, net of salvage	(93)	(136)
Change in construction payables, net	(14)	(75)
Payments pursuant to LTSAs	(44)	(17)
Other investing activities	6	13
Net cash used for investing activities	(2,526)	(2,793)
Financing Activities:
Decrease in notes payable, net	(115)	(294)
Proceeds —
FFB loan	519	835
Senior notes	1,500	750
Pollution control revenue bonds	53	584
Short-term borrowings	250	250
Capital contributions from parent company	1,379	82
Redemptions and repurchases —
Short-term borrowings	(375)	0
Pollution control revenue bonds	(148)	(223)
Senior notes	(950)	0
FFB loan	(55)	0
Payment of common stock dividends	(1,156)	(1,182)
Other financing activities	(35)	(37)
Net cash provided from (used for) financing activities	867	765
Net Change in Cash, Cash Equivalents, and Restricted Cash	466	337
Cash, Cash Equivalents, and Restricted Cash at Beginning of Period	52	112
Cash, Cash Equivalents, and Restricted Cash at End of Period	518	449
Cash paid during the period for —
Interest, net of amounts capitalized	316	296
Income taxes, net	311	45
Accrued property additions at end of period	523	589
Right-of-use assets obtained under operating leases	30	18
Right-of-use assets obtained under finance leases	0	24
Interest capitalized	34	25
MISSISSIPPI POWER CO
Operating Activities:
Net income	138	139
Adjustments to reconcile net income to net cash provided from operating activities —
Depreciation and amortization, total	142	148
Deferred income taxes	(19)	10
Settlement of asset retirement obligations	(16)	(28)
Other, net	9	8
Changes in certain current assets and liabilities —
-Receivables	(3)	(11)
-Other current assets	(7)	18
-Accounts payable	(54)	(26)
-Accrued taxes	15	(12)
-Accrued compensation	(8)	(10)
-Other current liabilities	(11)	6
Net cash provided from operating activities	186	242
Investing Activities:
Property additions	(174)	(134)
Change in construction payables, net	7	(16)
Payments pursuant to LTSAs	(20)	(18)
Other investing activities	(13)	(30)
Net cash used for investing activities	(200)	(198)
Proceeds —
Pollution control revenue bonds	34	43
Short-term borrowings	40	0
Capital contributions from parent company	80	2
Other long-term debt	100	0
Redemptions and repurchases —
Short-term borrowings	(40)	0
Pollution control revenue bonds	(41)	0
Senior notes	(275)	0
Return of capital to parent company	(74)	(113)
Payment of common stock dividends	(37)	0
Other financing activities	(1)	(1)
Net cash provided from (used for) financing activities	(214)	(69)
Net Change in Cash, Cash Equivalents, and Restricted Cash	(228)	(25)
Cash, Cash Equivalents, and Restricted Cash at Beginning of Period	286	293
Cash, Cash Equivalents, and Restricted Cash at End of Period	58	268
Cash paid during the period for —
Interest, net of amounts capitalized	49	55
Income taxes, net	9	0
Accrued property additions at end of period	42	20
Interest capitalized	0	1
SOUTHERN POWER CO
Operating Activities:
Net income	215	342
Adjustments to reconcile net income to net cash provided from operating activities —
Depreciation and amortization, total	386	377
Deferred income taxes	(59)	(122)
Utilization of federal investment tax credits	318	705
Amortization of investment tax credits	(44)	(136)
(Gain) loss on dispositions, net	(39)	(24)
Other, net	(16)	(19)
Changes in certain current assets and liabilities —
-Receivables	(28)	15
-Prepaid income taxes	74	33
-Other current assets	(17)	(3)
-Accounts payable	(12)	(5)
-Accrued taxes	21	66
-Other current liabilities	(25)	(8)
Net cash provided from operating activities	774	1,221
Investing Activities:
Business acquisitions, net of cash acquired	(81)	(50)
Property additions	(135)	(284)
Proceeds from dispositions and asset sales	663	572
Investment in unconsolidated subsidiaries	0	(116)
Payments pursuant to LTSAs	(61)	(85)
Other investing activities	38	(1)
Net cash used for investing activities	424	36
Financing Activities:
Decrease in notes payable, net	(449)	0
Proceeds —
Capital contributions from parent company	0	59
Redemptions and repurchases —
Short-term borrowings	(100)	(100)
Senior notes	(300)	0
Return of capital to parent company	0	(755)
Distributions to noncontrolling interests	(164)	(125)
Capital contributions from noncontrolling interests	173	11
Purchase of membership interests from noncontrolling interests	(60)	0
Payment of common stock dividends	(151)	(154)
Other financing activities	(9)	(6)
Net cash provided from (used for) financing activities	(1,060)	(1,070)
Net Change in Cash, Cash Equivalents, and Restricted Cash	138	187
Cash, Cash Equivalents, and Restricted Cash at Beginning of Period	279	181
Cash, Cash Equivalents, and Restricted Cash at End of Period	417	368
Cash paid during the period for —
Interest, net of amounts capitalized	123	133
Income taxes, net	(278)	(612)
Accrued property additions at end of period	44	41
Right-of-use assets obtained under operating leases	30	0
Interest capitalized	10	11
SOUTHERN Co GAS
Operating Activities:
Net income	360	347
Adjustments to reconcile net income to net cash provided from operating activities —
Depreciation and amortization, total	368	359
Deferred income taxes	(1)	96
Mark-to-market adjustments	104	44
Impairment charges	0	92
Other, net	(20)	(58)
Changes in certain current assets and liabilities —
-Receivables	403	832
-Natural gas for sale	26	49
-Other current assets	(45)	45
-Accounts payable	(75)	(607)
-Accrued taxes	7	(68)
-Accrued compensation	(17)	(34)
-Other current liabilities	12	(48)
Net cash provided from operating activities	1,122	1,049
Investing Activities:
Property additions	(1,045)	(1,008)
Proceeds from dispositions and asset sales	178	32
Cost of removal, net of salvage	(60)	(59)
Change in construction payables, net	25	57
Investment in unconsolidated subsidiaries	(79)	(25)
Other investing activities	8	14
Net cash used for investing activities	(973)	(989)
Financing Activities:
Decrease in notes payable, net	(500)	(383)
Proceeds —
Senior notes	500	0
First mortgage bonds	150	200
Capital contributions from parent company	215	820
Redemptions and repurchases —
First mortgage bonds	0	(50)
Senior notes	0	(300)
Payment of common stock dividends	(399)	(353)
Other financing activities	(3)	(2)
Net cash provided from (used for) financing activities	(37)	(68)
Net Change in Cash, Cash Equivalents, and Restricted Cash	112	(8)
Cash, Cash Equivalents, and Restricted Cash at Beginning of Period	49	70
Cash, Cash Equivalents, and Restricted Cash at End of Period	161	62
Cash paid during the period for —
Interest, net of amounts capitalized	162	180
Income taxes, net	45	48
Accrued property additions at end of period	146	154
Interest capitalized	$ 5	$ 5