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, 2020			1,000
Balance at Dec. 31, 2020		$ 2,939	$ 0	$ 2,308	$ 634	$ (3)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	$ 2,285	84			84
Dividends declared		(13)			(13)
Balance (shares) at Jun. 30, 2021			1,000
Balance at Jun. 30, 2021		3,010	$ 0	2,308	705	(3)
Balance (shares) at Mar. 31, 2021			1,000
Balance at Mar. 31, 2021		2,941	$ 0	2,308	636	(3)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	$ 2,281	82			82
Dividends declared		(13)			(13)
Balance (shares) at Jun. 30, 2021			1,000
Balance at Jun. 30, 2021		$ 3,010	$ 0	2,308	705	(3)
Balance (shares) at Dec. 31, 2021	76,000,000	1,000	1,000
Balance at Dec. 31, 2021	$ 46,694	$ 3,030	$ 0	2,308	724	(2)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	$ 2,768	74			74
Contributions		$ 25		25
Balance (shares) at Jun. 30, 2022	76,000,000	1,000	1,000
Balance at Jun. 30, 2022	$ 47,304	$ 3,129	$ 0	2,333	798	(2)
Balance (shares) at Mar. 31, 2022			1,000
Balance at Mar. 31, 2022		3,028	$ 0	2,308	722	(2)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	$ 2,897	76			76
Contributions		$ 25		25
Balance (shares) at Jun. 30, 2022	76,000,000	1,000	1,000
Balance at Jun. 30, 2022	$ 47,304	$ 3,129	$ 0	$ 2,333	$ 798	$ (2)