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Property, Plant and Equipment, Net Property, Plant and Equipment - MEC (Details) - MidAmerican Energy Company [Member] - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Public Utility, Property, Plant and Equipment [Line Items]      
Public Utilities, Property, Plant and Equipment, Net, Excluding Construction Work In Progress $ 12,328 $ 11,056  
Public Utilities, Property, Plant and Equipment, Net $ 12,821 $ 11,723  
Regulated Electric [Member]      
Public Utility, Property, Plant and Equipment [Line Items]      
Public Utilities, Property, Plant and Equipment, Disclosure of Composite Depreciation Rate for Plants in Service 2.80% 3.00% 2.80%
Natural Gas Processing Plant [Member]      
Public Utility, Property, Plant and Equipment [Line Items]      
Public Utilities, Property, Plant and Equipment, Disclosure of Composite Depreciation Rate for Plants in Service 2.90% 2.90% 2.80%
Regulated Operation [Member]      
Public Utility, Property, Plant and Equipment [Line Items]      
Public Utilities, Property, Plant and Equipment, Plant in Service, Excluding Construction Work In Progress $ 17,770 $ 16,275  
Public Utilities, Property, Plant and Equipment, Accumulated Depreciation (5,448) (5,229)  
Public Utilities, Property, Plant and Equipment, Net, Excluding Construction Work In Progress 12,322 11,046  
Public Utilities, Property, Plant and Equipment, Construction Work in Progress 493 667  
Regulated Operation [Member] | Electric Operations [Member]      
Public Utility, Property, Plant and Equipment [Line Items]      
Public Utilities, Property, Plant and Equipment, Generation or Processing 11,282 10,404  
Public Utilities, Property, Plant and Equipment, Transmission 1,726 1,305  
Public Utilities, Property, Plant and Equipment, Distribution 3,197 3,059  
Regulated Operation [Member] | Natural Gas Processing Plant [Member]      
Public Utility, Property, Plant and Equipment [Line Items]      
Public Utilities, Property, Plant and Equipment, Distribution 1,565 1,507  
Nonregulated Operation [Member]      
Public Utility, Property, Plant and Equipment [Line Items]      
Public Utilities, Property, Plant and Equipment, Accumulated Depreciation (1) (5)  
Public Utilities, Property, Plant and Equipment, Net, Excluding Construction Work In Progress 6 10  
Gross public utility property, plant and equipment in service $ 7 $ 15  
Minimum [Member] | Regulated Operation [Member] | Electric Operations [Member]      
Public Utility, Property, Plant and Equipment [Line Items]      
Public Utilities, Property, Plant and Equipment, Generation, Useful Life 20 years    
Public Utilities, Property, Plant and Equipment, Transmission, Useful Life 52 years    
Public Utilities, Property, Plant and Equipment, Distribution, Useful Life 20 years    
Minimum [Member] | Regulated Operation [Member] | Natural Gas Processing Plant [Member]      
Public Utility, Property, Plant and Equipment [Line Items]      
Public Utilities, Property, Plant and Equipment, Distribution, Useful Life 28 years    
Minimum [Member] | Nonregulated Operation [Member]      
Public Utility, Property, Plant and Equipment [Line Items]      
Public Utilities, Property, Plant and Equipment, Other Property Plant and Equipment, Useful Life 25 years    
Maximum [Member] | Regulated Operation [Member] | Electric Operations [Member]      
Public Utility, Property, Plant and Equipment [Line Items]      
Public Utilities, Property, Plant and Equipment, Generation, Useful Life 70 years    
Public Utilities, Property, Plant and Equipment, Transmission, Useful Life 75 years    
Public Utilities, Property, Plant and Equipment, Distribution, Useful Life 75 years    
Maximum [Member] | Regulated Operation [Member] | Natural Gas Processing Plant [Member]      
Public Utility, Property, Plant and Equipment [Line Items]      
Public Utilities, Property, Plant and Equipment, Distribution, Useful Life 70 years    
Maximum [Member] | Nonregulated Operation [Member]      
Public Utility, Property, Plant and Equipment [Line Items]      
Public Utilities, Property, Plant and Equipment, Other Property Plant and Equipment, Useful Life 50 years    
Electricity Generation Plant, Non-Nuclear [Member] | Regulated Operation [Member]      
Public Utility, Property, Plant and Equipment [Line Items]      
Change in Accounting Estimates, Impact on Period of Change $ 3    
Change in Accounting Estimates, Impact on Future Periods $ 34