Employee Benefit Plans - MEC - Contributions and Benefit Payments (Details) $ in Millions	Dec. 31, 2019 USD ($)
Pension Plan [Member] | MidAmerican Energy Company [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year	$ 7
Defined Benefit Plan, Expected Future Benefit Payment, Next Twelve Months	64
Defined Benefit Plan, Expected Future Benefit Payment, Year Two	63
Defined Benefit Plan, Expected Future Benefit Payment, Year Three	61
Defined Benefit Plan, Expected Future Benefit Payment, Year Four	58
Defined Benefit Plan, Expected Future Benefit Payment, Year Five	56
Defined Benefit Plan, Expected Future Benefit Payment, Five Fiscal Years Thereafter	244
Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Expected Future Benefit Payment, Next Twelve Months	57
Defined Benefit Plan, Expected Future Benefit Payment, Year Two	56
Defined Benefit Plan, Expected Future Benefit Payment, Year Three	55
Defined Benefit Plan, Expected Future Benefit Payment, Year Four	54
Defined Benefit Plan, Expected Future Benefit Payment, Year Five	51
Defined Benefit Plan, Expected Future Benefit Payment, Five Fiscal Years Thereafter	224
Other Postretirement Benefits Plan [Member] | MidAmerican Energy Company [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year	1
Defined Benefit Plan, Expected Future Benefit Payment, Next Twelve Months	20
Defined Benefit Plan, Expected Future Benefit Payment, Year Two	22
Defined Benefit Plan, Expected Future Benefit Payment, Year Three	22
Defined Benefit Plan, Expected Future Benefit Payment, Year Four	21
Defined Benefit Plan, Expected Future Benefit Payment, Year Five	20
Defined Benefit Plan, Expected Future Benefit Payment, Five Fiscal Years Thereafter	$ 84