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Short-Term Credit Arrangements and Borrowings (Details)
Jun. 30, 2017
USD ($)
Availability under combined facilities  
Maximum borrowing capacity $ 2,120,000,000
Amounts outstanding 522,000,000
Net availability 1,598,000,000
DTE Energy  
Availability under combined facilities  
Maximum borrowing capacity 1,420,000,000
Amounts outstanding 102,000,000
Net availability 1,318,000,000
DTE Electric  
Availability under combined facilities  
Maximum borrowing capacity 400,000,000
Amounts outstanding 326,000,000
Net availability 74,000,000
DTE Gas  
Availability under combined facilities  
Maximum borrowing capacity 300,000,000
Amounts outstanding 94,000,000
Net availability 206,000,000
Letter of credit  
Availability under combined facilities  
Amounts outstanding 102,000,000
Letter of credit | DTE Energy  
Availability under combined facilities  
Amounts outstanding 102,000,000
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
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 Energy  
Availability under combined facilities  
Maximum borrowing capacity 1,200,000,000
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
Commercial paper issuances  
Availability under combined facilities  
Amounts outstanding 420,000,000
Commercial paper issuances | DTE Energy  
Availability under combined facilities  
Amounts outstanding 0
Commercial paper issuances | DTE Electric  
Availability under combined facilities  
Amounts outstanding 326,000,000
Commercial paper issuances | DTE Gas  
Availability under combined facilities  
Amounts outstanding $ 94,000,000