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New Accounting Pronouncements - Narrative (Details) - USD ($)
$ in Millions
6 Months Ended
Jun. 30, 2018
Dec. 31, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items]    
Implementation of ASU 2016-01   $ 0
True-up adjustment to the remeasurement of deferred taxes $ 21  
DTE Electric    
New Accounting Pronouncements or Change in Accounting Principle [Line Items]    
Implementation of ASU 2016-01   0
True-up adjustment to the remeasurement of deferred taxes 8  
Other Regulatory Assets (Liabilities)    
New Accounting Pronouncements or Change in Accounting Principle [Line Items]    
True-up adjustment to the remeasurement of deferred taxes $ 16  
Accumulated Other Comprehensive Income (Loss)    
New Accounting Pronouncements or Change in Accounting Principle [Line Items]    
Implementation of ASU 2016-01   (5)
Accumulated Other Comprehensive Income (Loss) | DTE Electric    
New Accounting Pronouncements or Change in Accounting Principle [Line Items]    
Implementation of ASU 2016-01   (3)
Accumulated Other Comprehensive Income (Loss) | Accounting Standards Update 2016-01    
New Accounting Pronouncements or Change in Accounting Principle [Line Items]    
Implementation of ASU 2016-01   (5)
Accumulated Other Comprehensive Income (Loss) | Accounting Standards Update 2016-01 | DTE Electric    
New Accounting Pronouncements or Change in Accounting Principle [Line Items]    
Implementation of ASU 2016-01   (3)
Retained Earnings    
New Accounting Pronouncements or Change in Accounting Principle [Line Items]    
Implementation of ASU 2016-01   5
Retained Earnings | DTE Electric    
New Accounting Pronouncements or Change in Accounting Principle [Line Items]    
Implementation of ASU 2016-01   3
Retained Earnings | Accounting Standards Update 2016-01    
New Accounting Pronouncements or Change in Accounting Principle [Line Items]    
Implementation of ASU 2016-01   5
Retained Earnings | Accounting Standards Update 2016-01 | DTE Electric    
New Accounting Pronouncements or Change in Accounting Principle [Line Items]    
Implementation of ASU 2016-01   $ 3