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Investments and Restricted Cash and Investments Investments and Restricted Cash and Investments - MEC - (Details) - USD ($)
$ in Millions
Dec. 31, 2019
Dec. 31, 2018
Investments, Including Equity Method And Restricted Cash And Investments [Line Items]    
Investments, including equity method and restricted cash and investments, noncurrent $ 6,255 $ 4,903
Nuclear decommissioning trust funds [Member]    
Investments, Including Equity Method And Restricted Cash And Investments [Line Items]    
Decommissioning Fund Investments, Fair Value 599 504
MidAmerican Energy Company [Member]    
Investments, Including Equity Method And Restricted Cash And Investments [Line Items]    
Life Insurance, Corporate or Bank Owned, Amount 203 191
Other Investments 16 13
Investments, including equity method and restricted cash and investments, noncurrent $ 818 $ 708
MidAmerican Energy Company [Member] | Domestic Equity Securities [Member]    
Investments, Including Equity Method And Restricted Cash And Investments [Line Items]    
Nuclear Decommissioning Trust Fund Ownership Percentage 56.00% 51.00%
MidAmerican Energy Company [Member] | US Government Corporations and Agencies Securities [Member]    
Investments, Including Equity Method And Restricted Cash And Investments [Line Items]    
Nuclear Decommissioning Trust Fund Ownership Percentage 31.00% 37.00%
MidAmerican Energy Company [Member] | Debt Security, Corporate, US [Member]    
Investments, Including Equity Method And Restricted Cash And Investments [Line Items]    
Nuclear Decommissioning Trust Fund Ownership Percentage 10.00% 9.00%
MidAmerican Energy Company [Member] | Other Securities [Member]    
Investments, Including Equity Method And Restricted Cash And Investments [Line Items]    
Nuclear Decommissioning Trust Fund Ownership Percentage 3.00% 3.00%
MidAmerican Energy Company [Member] | Nuclear decommissioning trust funds [Member]    
Investments, Including Equity Method And Restricted Cash And Investments [Line Items]    
Decommissioning Fund Investments, Fair Value $ 599 $ 504