Employee Benefit Plans - BHE (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Other Postretirement Plans
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 2	$ 1	$ 8	$ 5
Interest cost	4	6	14	16
Expected return on plan assets	(5)	(9)	(16)	(25)
Net amortization	0	(1)	(2)	(5)
Net periodic benefit cost (credit)	1	(3)	4	(9)
United States | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Service cost	7	4	22	11
Interest cost	21	23	59	69
Expected return on plan assets	(32)	(35)	(101)	(105)
Settlement	4	0	4	0
Net amortization	6	8	19	25
Net periodic benefit cost (credit)	6	0	3	0
United Kingdom | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Service cost	4	4	12	12
Interest cost	8	10	23	30
Expected return on plan assets	(28)	(26)	(84)	(76)
Net amortization	14	11	42	32
Net periodic benefit cost (credit)	$ (2)	$ (1)	$ (7)	$ (2)