Statements of Common Stockholders' Equity - MPC - USD ($) shares in Millions, $ in Millions	Total	Common Stock	Retained Earnings	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, 2022		1,090			1
Beginning balance at Dec. 31, 2022				$ 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
Current period change				0
Cash dividends on common stock	(3,035)		$ (3,035)	(185)			(185)
Ending balance (in shares) at Dec. 31, 2023		1,092			1
Ending balance at Dec. 31, 2023				2,003	$ 38	4,721	(2,756)	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income	4,401			199			199
Capital contributions from parent company				70		70
Current period change				5				5
Cash dividends on common stock	(3,133)		(3,133)	$ (188)			(188)
Ending balance (in shares) at Dec. 31, 2024		1,098		1	1
Ending balance at Dec. 31, 2024	33,208			$ 2,089	$ 38	4,791	(2,745)	5
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income	4,341			215			215
Capital contributions from parent company				80		80
Current period change				(1)				(1)
Cash dividends on common stock	(3,237)		$ (3,237)	$ (194)			(194)
Ending balance (in shares) at Dec. 31, 2025		1,120		1	1
Ending balance at Dec. 31, 2025	$ 36,016			$ 2,189	$ 38	$ 4,871	$ (2,724)	$ 4