Consolidated Statements of Changes in Equity (Unaudited) - NPC - USD ($) $ in Millions	Total	NPC	NPC Common Stock	NPC Additional Paid-in Capital	NPC Retained Earnings	NPC Accumulated Other Comprehensive (Loss) Income, Net
Balance (shares) at Dec. 31, 2021			1,000
Balance at Dec. 31, 2021		$ 3,030	$ 0	$ 2,308	$ 724	$ (2)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	$ (129)	(2)			(2)
Balance (shares) at Mar. 31, 2022			1,000
Balance at Mar. 31, 2022		$ 3,028	$ 0	2,308	722	(2)
Balance (shares) at Dec. 31, 2022	76,000,000	1,000	1,000
Balance at Dec. 31, 2022	$ 46,832	$ 3,354	$ 0	2,333	1,022	(1)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	$ 989	4			4
Contributions		$ 400		400
Balance (shares) at Mar. 31, 2023	76,000,000	1,000	1,000
Balance at Mar. 31, 2023	$ 47,853	$ 3,758	$ 0	$ 2,733	$ 1,026	$ (1)