Statements of Common Stockholders' Equity - MPC - USD ($) shares in Millions, $ in Millions	Total	Common Stock	Paid-In Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Mississippi Power	Mississippi Power Common Stock	Mississippi Power Paid-In Capital	Mississippi Power Retained Earnings	Mississippi Power Accumulated Other Comprehensive Income (Loss)
Beginning balance (in shares) at Dec. 31, 2020		1,058					1
Beginning balance at Dec. 31, 2020						$ 1,742	$ 38	$ 4,460	$ (2,754)	$ (2)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	$ 2,393					159			159
Capital contributions from parent company						122		122
Other comprehensive income (loss)	158				$ 158	1				1
Cash dividends on common stock	(2,777)			$ (2,777)		(157)			(157)
Other	(7)		$ (8)	2					(1)	1
Ending balance (in shares) at Dec. 31, 2021		1,061					1
Ending balance at Dec. 31, 2021						1,867	$ 38	4,582	(2,753)	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	3,524					164			164
Capital contributions from parent company						70		70
Other comprehensive income (loss)	71				71
Cash dividends on common stock	(2,907)			(2,907)		(170)			(170)
Other	(6)		9	(8)	(1)
Ending balance (in shares) at Dec. 31, 2022		1,090					1
Ending balance at Dec. 31, 2022	30,408					1,931	$ 38	4,652	(2,759)	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	3,976					188			188
Capital contributions from parent company						69		69
Other comprehensive income (loss)	(10)				$ (10)
Cash dividends on common stock	(3,035)			(3,035)		(185)			(185)
Other	(5)		$ (1)	$ 3
Ending balance (in shares) at Dec. 31, 2023		1,092					1
Ending balance at Dec. 31, 2023	$ 31,444					$ 2,003	$ 38	$ 4,721	$ (2,756)	$ 0