Employee Benefit Plans - BHE (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Other Postretirement Plans
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 4	$ 3	$ 6	$ 4
Interest cost	5	4	10	10
Expected return on plan assets	(6)	(7)	(11)	(16)
Net amortization	(1)	(3)	(2)	(4)
Net periodic benefit credit	2	(3)	3	(6)
United States | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Service cost	8	4	15	7
Interest cost	18	23	38	46
Expected return on plan assets	(36)	(35)	(69)	(70)
Net amortization	7	8	13	17
Net periodic benefit credit	(3)	0	(3)	0
United Kingdom | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Service cost	4	4	8	8
Interest cost	7	10	15	20
Expected return on plan assets	(28)	(25)	(56)	(50)
Net amortization	14	11	28	21
Net periodic benefit credit	$ (3)	$ 0	$ (5)	$ (1)