Employee Benefit Plans - BHE - Employer Contributions (Details) - 6 months ended Jun. 30, 2022 £ in Millions, $ in Millions	USD ($)	GBP (£)	GBP (£)
Other Postretirement Plans
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, expected contributions in current fiscal year	$ 5
Employer contributions	5
U.S. | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, expected contributions in current fiscal year	13
Employer contributions	7
United Kingdom | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, expected contributions in current fiscal year | £			£ 12
Employer contributions	$ 8	£ 6