Unaudited Quarterly Operating Results - MEC (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Quarterly Operating Results [Line Items]
Revenues									$ 18,614	$ 17,422	$ 17,880
Operating income (loss)									4,514	4,251	4,328
Net income attributable to BHE shareholders									2,870	2,542	2,370
MidAmerican Energy Company [Member]
Quarterly Operating Results [Line Items]
Revenues	$ 671	$ 813	$ 658	$ 695	$ 621	$ 795	$ 584	$ 625	2,837	2,625	2,502
Operating income (loss)	31	288	135	107	42	284	139	100	561	565	449
Net income attributable to BHE shareholders	$ (19)	$ 385	$ 134	$ 105	$ 15	$ 320	$ 131	$ 76	$ 605	$ 542	$ 462