Consolidated Statements of Changes in Shareholder's Equity - SPPC - USD ($) $ in Millions	Total	Additional Paid-in Capital	Retained Earnings	SPPC	SPPC Common Stock	SPPC Additional Paid-in Capital	SPPC Retained Earnings	SPPC Accumulated Other Comprehensive Income (Loss)
Balance (shares) at Dec. 31, 2021					1,000
Balance at Dec. 31, 2021				$ 1,535	$ 0	$ 1,111	$ 425	$ (1)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	$ 2,721			118			118
Dividends declared				(70)			(70)
Other equity transactions	(6)	$ 1	$ (12)
Contributions				465		465
Balance (shares) at Dec. 31, 2022					1,000
Balance at Dec. 31, 2022				2,048	$ 0	1,576	473	(1)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	3,020			117			117
Dividends declared				$ (100)			(100)
Other equity transactions	$ (9)
Balance (shares) at Dec. 31, 2023	75,627,913			1,000	1,000
Balance at Dec. 31, 2023	$ 48,434			$ 2,065	$ 0	1,576	490	(1)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	4,300			85			85
Dividends declared				(200)			(200)
Other equity transactions	$ (1)
Contributions				$ 150		150
Balance (shares) at Dec. 31, 2024	1			1,000	1,000
Balance at Dec. 31, 2024	$ 50,009			$ 2,100	$ 0	$ 1,726	$ 375	$ (1)