Consolidated Statements of Changes in Equity - NPC - USD ($) $ in Millions	Total	Common Stock [Member]	Nevada Power Company [Member]	Nevada Power Company [Member] Common Stock [Member]	Nevada Power Company [Member] Additional Paid-in Capital [Member]	Nevada Power Company [Member] Retained Earnings [Member]	Nevada Power Company [Member] Accumulated Other Comprehensive (Loss) Income, Net [Member]
Balance (shares) at Dec. 31, 2015		77,000,000		1,000
Stockholders' Equity Attributable to Parent at Dec. 31, 2015			$ 3,163	$ 0	$ 2,308	$ 858	$ (3)
Net Income (Loss) Attributable to Parent	$ 490		3			3
Balance (shares) at Mar. 31, 2016		77,000,000		1,000
Stockholders' Equity Attributable to Parent at Mar. 31, 2016			$ 3,166	$ 0	2,308	861	(3)
Balance (shares) at Dec. 31, 2016	77,000,000	77,000,000	1,000	1,000
Stockholders' Equity Attributable to Parent at Dec. 31, 2016	$ 24,327		$ 2,972	$ 0	2,308	667	(3)
Net Income (Loss) Attributable to Parent	$ 556		10			10
Dividends, Common Stock, Cash			$ 75			75
Balance (shares) at Mar. 31, 2017	77,000,000	77,000,000	1,000	1,000
Stockholders' Equity Attributable to Parent at Mar. 31, 2017	$ 24,982		$ 2,907	$ 0	$ 2,308	$ 602	$ (3)