Condensed Consolidated Statements of Cash Flows (Unaudited) - SPC - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Operating Activities:
Net income (loss)	$ 991	$ 1,107
Adjustments to reconcile net income to net cash provided from operating activities —
Depreciation and amortization, total	989	964
Deferred income taxes	40	140
Gain on dispositions, net	(20)	(41)
Other, net	7	114
Changes in certain current assets and liabilities —
-Receivables	(217)	308
-Other current assets	87	90
-Accounts payable	132	(216)
-Accrued taxes	(58)	(212)
-Other current liabilities	35	(63)
Net cash provided from operating activities	1,592	1,242
Investing Activities:
Business acquisitions, net of cash acquired	0	(345)
Property additions	(1,419)	(1,678)
Payments pursuant to LTSAs	(37)	(60)
Other investing activities	110	45
Net cash used for investing activities	(1,555)	(2,243)
Financing Activities:
Increase in notes payable	137	182
Proceeds —
Capital contributions from noncontrolling interests	73	313
Distributions to noncontrolling interests	(97)	(46)
Payment of common stock dividends	(702)	(678)
Other financing activities	(115)	(117)
Net cash provided from (used for) financing activities	(193)	1,734
Net Change in Cash, Cash Equivalents, and Restricted Cash	(156)	733
Cash, Cash Equivalents, and Restricted Cash at Beginning of Period	1,829	1,068
Cash, Cash Equivalents, and Restricted Cash at End of Period	1,673	1,801
Supplemental Cash Flow Information:
Interest, net of amounts capitalized	515	519
Income taxes, net	(8)	(51)
Noncash transactions —
Contributions from noncontrolling interests	0	89
Contributions of wind turbine equipment	0	82
Accrued property additions at year-end	863	872
Reassessment of right-of-use assets under operating leases	40	0
Southern Power
Operating Activities:
Net income (loss)	27	65
Adjustments to reconcile net income to net cash provided from operating activities —
Depreciation and amortization, total	126	125
Deferred income taxes	12	(8)
Amortization of investment tax credits	(15)	(15)
Gain on dispositions, net	(2)	(39)
Other, net	(3)	(4)
Changes in certain current assets and liabilities —
-Receivables	11	23
-Prepaid income taxes	(8)	16
-Other current assets	0	3
-Accounts payable	(21)	19
-Accrued taxes	7	5
-Other current liabilities	(17)	(3)
Net cash provided from operating activities	117	187
Investing Activities:
Business acquisitions, net of cash acquired	0	(345)
Property additions	(19)	(147)
Proceeds from dispositions	29	17
Change in construction payables	(31)	(7)
Payments pursuant to LTSAs	(15)	(27)
Other investing activities	(1)	5
Net cash used for investing activities	(37)	(504)
Financing Activities:
Increase (decrease) in notes payable, net	(3)
Increase in notes payable		140
Proceeds —
Senior notes	0	400
Return of capital to parent company	0	(271)
Capital contributions from noncontrolling interests	73	313
Distributions to noncontrolling interests	(97)	(46)
Payment of common stock dividends	(49)	(51)
Other financing activities	0	(7)
Net cash provided from (used for) financing activities	(76)	478
Net Change in Cash, Cash Equivalents, and Restricted Cash	4	161
Cash, Cash Equivalents, and Restricted Cash at Beginning of Period	135	182
Cash, Cash Equivalents, and Restricted Cash at End of Period	139	343
Supplemental Cash Flow Information:
Interest, net of amounts capitalized	29	26
Income taxes, net	(8)	(2)
Noncash transactions —
Contributions from noncontrolling interests	0	89
Contributions of wind turbine equipment	0	82
Accrued property additions at year-end	46	60
Right-of-use assets obtained under operating leases	0	65
Reassessment of right-of-use assets under operating leases	$ 40	$ 0