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Short-Term Credit Arrangements and Borrowings (Details) - USD ($)
Mar. 31, 2017
Feb. 28, 2017
Availability under combined facilities    
Maximum borrowing capacity $ 2,120,000,000  
Amounts outstanding 198,000,000  
Net availability 1,922,000,000  
DTE Energy    
Availability under combined facilities    
Maximum borrowing capacity 1,420,000,000  
Amounts outstanding 139,000,000  
Net availability 1,281,000,000  
DTE Electric    
Availability under combined facilities    
Maximum borrowing capacity 400,000,000  
Amounts outstanding 59,000,000  
Net availability 341,000,000  
DTE Gas    
Availability under combined facilities    
Maximum borrowing capacity 300,000,000  
Amounts outstanding 0  
Net availability 300,000,000  
Letter of credit    
Availability under combined facilities    
Amounts outstanding 139,000,000  
Letter of credit | DTE Energy    
Availability under combined facilities    
Amounts outstanding 139,000,000  
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 | Unsecured letter of credit facility, expiring in February 2019    
Availability under combined facilities    
Maximum borrowing capacity 150,000,000  
Letter of credit | Unsecured letter of credit facility, expiring in February 2019 | DTE Energy    
Availability under combined facilities    
Maximum borrowing capacity 150,000,000  
Letter of credit | Unsecured letter of credit facility, expiring in February 2019 | DTE Electric    
Availability under combined facilities    
Maximum borrowing capacity 0  
Letter of credit | Unsecured letter of credit facility, expiring in February 2019 | DTE Gas    
Availability under combined facilities    
Maximum borrowing capacity 0  
Letter of credit | Unsecured letter of credit facility, expiring in September 2017    
Availability under combined facilities    
Maximum borrowing capacity 70,000,000  
Letter of credit | Unsecured letter of credit facility, expiring in September 2017 | DTE Energy    
Availability under combined facilities    
Maximum borrowing capacity 70,000,000  
Letter of credit | Unsecured letter of credit facility, expiring in September 2017 | DTE Electric    
Availability under combined facilities    
Maximum borrowing capacity 0  
Letter of credit | Unsecured letter of credit facility, expiring in September 2017 | DTE Gas    
Availability under combined facilities    
Maximum borrowing capacity 0  
Letter of credit | Unsecured letter of credit facility, expiring in February 2017 | DTE Energy    
Availability under combined facilities    
Maximum borrowing capacity   $ 100,000,000
Revolving credit facility | Unsecured revolving credit facility, expiring in April 2021    
Availability under combined facilities    
Maximum borrowing capacity 1,900,000,000  
Revolving credit facility | Unsecured revolving credit facility, expiring in April 2021 | DTE Energy    
Availability under combined facilities    
Maximum borrowing capacity 1,200,000,000  
Revolving credit facility | Unsecured revolving credit facility, expiring in April 2021 | DTE Electric    
Availability under combined facilities    
Maximum borrowing capacity 400,000,000  
Revolving credit facility | Unsecured revolving credit facility, expiring in April 2021 | DTE Gas    
Availability under combined facilities    
Maximum borrowing capacity 300,000,000  
Commercial paper issuances    
Availability under combined facilities    
Amounts outstanding 59,000,000  
Commercial paper issuances | DTE Energy    
Availability under combined facilities    
Amounts outstanding 0  
Commercial paper issuances | DTE Electric    
Availability under combined facilities    
Amounts outstanding 59,000,000  
Commercial paper issuances | DTE Gas    
Availability under combined facilities    
Amounts outstanding $ 0