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Regulatory Matters (Details Textuals)
$ in Millions
Jul. 24, 2018
USD ($)
Jul. 06, 2018
USD ($)
Jun. 28, 2018
USD ($)
May 30, 2018
USD ($)
May 24, 2018
USD ($)
May 18, 2018
USD ($)
Apr. 18, 2018
USD ($)
Mar. 28, 2018
USD ($)
Nov. 22, 2017
USD ($)
Nov. 01, 2017
USD ($)
Apr. 19, 2017
USD ($)
Jun. 30, 2018
USD ($)
Apr. 27, 2018
USD ($)
certificate
Jul. 31, 2017
USD ($)
certificate
MW
DTE Electric                            
Public Utilities, General Disclosures [Line Items]                            
Reduction of revenue due to Tax Cuts and Jobs Act, requested           $ 157.0                
DTE Electric | Subsequent event                            
Public Utilities, General Disclosures [Line Items]                            
Reduction of revenue due to Tax Cuts and Jobs Act, approved $ 157.0                          
DTE Electric | MPSC | Electric Rate Case Filing 2017                            
Public Utilities, General Disclosures [Line Items]                            
Requested rate increase                   $ 125.0 $ 231.0      
Approved rate increase     $ 74.4       $ 65.2              
Return on equity percent             10.00%              
DTE Electric | MPSC | Electric Rate Case Filing 2017 | Refundable self-implemented rates                            
Public Utilities, General Disclosures [Line Items]                            
Regulatory liabilities                       $ 25.0    
DTE Electric | MPSC | Electric Rate Case Filing 2018 | Subsequent event                            
Public Utilities, General Disclosures [Line Items]                            
Requested rate increase   $ 328.0                        
Return on equity percent   10.00%                        
Return on equity requested percent   10.50%                        
DTE Electric | MPSC | Certificate of Necessity Request                            
Public Utilities, General Disclosures [Line Items]                            
Amount of power associated with natural gas fueled combined cycle generation facility requesting to build | MW                           1,100
Number of certificates of necessity requested to be issued | certificate                           3
Estimated capital costs                           $ 989.0
Number of certificates of necessity approved for issuance | certificate                         3  
Approved recoverable amounts, maximum rate                         $ 951.8  
DTE Gas                            
Public Utilities, General Disclosures [Line Items]                            
Reduction of revenue due to Tax Cuts and Jobs Act, requested               $ 38.2            
Reduction of revenue due to Tax Cuts and Jobs Act, approved       $ 38.2                    
DTE Gas | MPSC | DTE Gas Rate Case Filing 2017                            
Public Utilities, General Disclosures [Line Items]                            
Requested rate increase         $ 38.1       $ 85.1          
Return on equity percent                 10.10%          
Return on equity requested percent                 10.50%