XML 102 R66.htm IDEA: XBRL DOCUMENT v3.19.1
Property, Plant and Equipment, Net (Details) - USD ($)
$ in Millions
3 Months Ended
Mar. 31, 2019
Dec. 31, 2018
Property, Plant and Equipment [Line Items]    
Property, plant and equipment in service, net $ 65,560 $ 64,977
Construction in Progress, Gross 3,388 3,110
Property, plant and equipment, net 68,948 68,087
Regulated Operation [Member]    
Property, Plant and Equipment [Line Items]    
Property, plant and equipment 85,206 84,231
Accumulated depreciation and amortization (26,253) (25,894)
Property, plant and equipment in service, net 58,953 58,337
Construction in Progress, Gross 3,200 2,900
Regulated Operation [Member] | Utility generation, transmission and distribution systems    
Property, Plant and Equipment [Line Items]    
Property, plant and equipment $ 77,659 76,707
Regulated Operation [Member] | Utility generation, transmission and distribution systems | Minimum [Member]    
Property, Plant and Equipment [Line Items]    
Depreciable Life 5 years  
Regulated Operation [Member] | Utility generation, transmission and distribution systems | Maximum [Member]    
Property, Plant and Equipment [Line Items]    
Depreciable Life 80 years  
Regulated Operation [Member] | Interstate natural gas pipeline assets    
Property, Plant and Equipment [Line Items]    
Property, plant and equipment $ 7,547 7,524
Regulated Operation [Member] | Interstate natural gas pipeline assets | Minimum [Member]    
Property, Plant and Equipment [Line Items]    
Depreciable Life 3 years  
Regulated Operation [Member] | Interstate natural gas pipeline assets | Maximum [Member]    
Property, Plant and Equipment [Line Items]    
Depreciable Life 80 years  
Unregulated Operation [Member]    
Property, Plant and Equipment [Line Items]    
Property, plant and equipment $ 8,318 8,250
Accumulated depreciation and amortization (1,711) (1,610)
Property, plant and equipment in service, net 6,607 6,640
Unregulated Operation [Member] | Independent power plants    
Property, Plant and Equipment [Line Items]    
Property, plant and equipment $ 6,844 6,826
Unregulated Operation [Member] | Independent power plants | Minimum [Member]    
Property, Plant and Equipment [Line Items]    
Depreciable Life 5 years  
Unregulated Operation [Member] | Independent power plants | Maximum [Member]    
Property, Plant and Equipment [Line Items]    
Depreciable Life 30 years  
Unregulated Operation [Member] | Other assets    
Property, Plant and Equipment [Line Items]    
Property, plant and equipment $ 1,474 $ 1,424
Unregulated Operation [Member] | Other assets | Minimum [Member]    
Property, Plant and Equipment [Line Items]    
Depreciable Life 3 years  
Unregulated Operation [Member] | Other assets | Maximum [Member]    
Property, Plant and Equipment [Line Items]    
Depreciable Life 30 years