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Short-Term Credit Arrangements and Borrowings (Details Textuals)
Jun. 30, 2018
USD ($)
Dec. 31, 2017
USD ($)
Short-term Debt [Line Items]    
Other outstanding letters of credit $ 621,000,000  
Letter of credit    
Short-term Debt [Line Items]    
Other outstanding letters of credit $ 147,000,000  
DTE Electric    
Short-term Debt [Line Items]    
Ratio of indebtedness to net capital 0.51  
Other outstanding letters of credit $ 130,000,000  
DTE Electric | Letter of credit    
Short-term Debt [Line Items]    
Other outstanding letters of credit $ 0  
DTE Gas    
Short-term Debt [Line Items]    
Ratio of indebtedness to net capital 0.45  
Other outstanding letters of credit $ 167,000,000  
DTE Gas | Letter of credit    
Short-term Debt [Line Items]    
Other outstanding letters of credit $ 0  
DTE Energy    
Short-term Debt [Line Items]    
Ratio of indebtedness to net capital 0.54  
Other outstanding letters of credit $ 324,000,000  
DTE Energy | Letter of credit    
Short-term Debt [Line Items]    
Other outstanding letters of credit 147,000,000  
DTE Energy | Demand financing agreement    
Short-term Debt [Line Items]    
Maximum borrowing capacity, financing agreement 100,000,000  
Maximum additional margin financing 50,000,000  
Amount outstanding 30,000,000 $ 56,000,000
DTE Energy | Demand financing agreement plus letter of credit    
Short-term Debt [Line Items]    
Maximum borrowing capacity, financing agreement 125,000,000  
DTE Energy | Other outstanding letters of credit | Letter of credit    
Short-term Debt [Line Items]    
Other outstanding letters of credit $ 9,000,000  
Maximum    
Short-term Debt [Line Items]    
Ratio of indebtedness to net capital 0.65