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Short-Term Credit Arrangements and Borrowings (Details) - USD ($)
Mar. 31, 2019
Feb. 28, 2019
Availability under combined facilities    
Maximum borrowing capacity $ 2,120,000,000  
Amounts outstanding 351,000,000  
Net availability 1,769,000,000  
DTE Electric    
Availability under combined facilities    
Maximum borrowing capacity 400,000,000  
Amounts outstanding 0  
Net availability 400,000,000  
DTE Gas    
Availability under combined facilities    
Maximum borrowing capacity 300,000,000  
Amounts outstanding 79,000,000  
Net availability 221,000,000  
DTE Energy    
Availability under combined facilities    
Maximum borrowing capacity 1,420,000,000  
Amounts outstanding 272,000,000  
Net availability 1,148,000,000  
Letter of credit    
Availability under combined facilities    
Amounts outstanding 195,000,000  
Letter of credit | DTE Electric    
Availability under combined facilities    
Amounts outstanding 0  
Letter of credit | DTE Gas    
Availability under combined facilities    
Amounts outstanding 0  
Letter of credit | DTE Energy    
Availability under combined facilities    
Amounts outstanding 195,000,000  
Letter of credit | Unsecured letter of credit facility, expiring in February 2021    
Availability under combined facilities    
Maximum borrowing capacity 150,000,000  
Letter of credit | Unsecured letter of credit facility, expiring in February 2021 | DTE Electric    
Availability under combined facilities    
Maximum borrowing capacity 0  
Letter of credit | Unsecured letter of credit facility, expiring in February 2021 | DTE Gas    
Availability under combined facilities    
Maximum borrowing capacity 0  
Letter of credit | Unsecured letter of credit facility, expiring in February 2021 | DTE Energy    
Availability under combined facilities    
Maximum borrowing capacity 150,000,000 $ 150,000,000
Letter of credit | Unsecured letter of credit facility, expiring in September 2019    
Availability under combined facilities    
Maximum borrowing capacity 70,000,000  
Letter of credit | Unsecured letter of credit facility, expiring in September 2019 | DTE Electric    
Availability under combined facilities    
Maximum borrowing capacity 0  
Letter of credit | Unsecured letter of credit facility, expiring in September 2019 | DTE Gas    
Availability under combined facilities    
Maximum borrowing capacity 0  
Letter of credit | Unsecured letter of credit facility, expiring in September 2019 | DTE Energy    
Availability under combined facilities    
Maximum borrowing capacity 70,000,000  
Revolving credit facility | Unsecured revolving credit facility, expiring April 2022    
Availability under combined facilities    
Maximum borrowing capacity 1,900,000,000  
Revolving credit facility | Unsecured revolving credit facility, expiring April 2022 | DTE Electric    
Availability under combined facilities    
Maximum borrowing capacity 400,000,000  
Revolving credit facility | Unsecured revolving credit facility, expiring April 2022 | DTE Gas    
Availability under combined facilities    
Maximum borrowing capacity 300,000,000  
Revolving credit facility | Unsecured revolving credit facility, expiring April 2022 | DTE Energy    
Availability under combined facilities    
Maximum borrowing capacity 1,200,000,000  
Commercial paper issuances    
Availability under combined facilities    
Amounts outstanding 156,000,000  
Commercial paper issuances | DTE Electric    
Availability under combined facilities    
Amounts outstanding 0  
Commercial paper issuances | DTE Gas    
Availability under combined facilities    
Amounts outstanding 79,000,000  
Commercial paper issuances | DTE Energy    
Availability under combined facilities    
Amounts outstanding $ 77,000,000