Condensed Statements of Cash Flows (Unaudited) - MPC - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Operating Activities:
Net income	$ 1,071	$ 799
Adjustments to reconcile net income to net cash provided from operating activities —
Depreciation and amortization, total	1,261	1,233
Pension, postretirement, and other employee benefits	(129)	(126)
Settlement of asset retirement obligations	(132)	(113)
Other, net	76	51
Changes in certain current assets and liabilities —
Receivables	52	790
Retail fuel cost under recovery	257	(470)
Other current assets	(27)	34
Accounts payable	(423)	(1,056)
Accrued taxes	(226)	(237)
Accrued compensation	(488)	(478)
Other current liabilities	103	75
Net cash provided from operating activities	1,311	844
Investing Activities:
Property additions	(1,770)	(1,850)
Cost of removal, net of salvage	(138)	(135)
Construction payables	(365)	(140)
Other investing activities	(111)	(91)
Net cash used for investing activities	(2,385)	(2,118)
Financing Activities:
Increase (decrease) in notes payable, net	236	187
Payment of common stock dividends	(733)	(742)
Other financing activities	(124)	(83)
Net cash provided from financing activities	985	454
Net Change in Cash, Cash Equivalents, and Restricted Cash	(89)	(820)
Cash, Cash Equivalents, and Restricted Cash at Beginning of Period	921	2,037
Cash, Cash Equivalents, and Restricted Cash at End of Period	832	1,217
Supplemental Cash Flow Information:
Interest, net of amounts capitalized	714	652
Noncash transactions —
Accrued property additions at end of period	580	833
Right-of-use assets obtained under operating leases	14	26
Mississippi Power
Operating Activities:
Net income	50	58
Adjustments to reconcile net income to net cash provided from operating activities —
Depreciation and amortization, total	50	58
Pension, postretirement, and other employee benefits	(4)	(5)
Settlement of asset retirement obligations	(4)	(3)
Other, net	4	0
Changes in certain current assets and liabilities —
Receivables	21	73
Retail fuel cost under recovery	3	(23)
Other current assets	(13)	(1)
Accounts payable	(34)	(74)
Accrued taxes	(59)	(62)
Accrued compensation	(21)	(17)
Other current liabilities	0	(7)
Net cash provided from operating activities	(7)	(3)
Investing Activities:
Property additions	(79)	(94)
Cost of removal, net of salvage	(12)	(6)
Construction payables	(7)	(9)
Payments pursuant to LTSAs	(5)	(8)
Other investing activities	(1)	0
Net cash used for investing activities	(104)	(117)
Financing Activities:
Increase (decrease) in notes payable, net	8	126
Proceeds — Senior notes	150	0
Payment of common stock dividends	(47)	(46)
Other financing activities	0	(1)
Net cash provided from financing activities	111	79
Net Change in Cash, Cash Equivalents, and Restricted Cash	0	(41)
Cash, Cash Equivalents, and Restricted Cash at Beginning of Period	38	59
Cash, Cash Equivalents, and Restricted Cash at End of Period	38	18
Supplemental Cash Flow Information:
Interest, net of amounts capitalized	29	25
Noncash transactions —
Accrued property additions at end of period	27	13
Right-of-use assets obtained under operating leases	$ 0	$ 1