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Regulatory Matters (Details Textuals)
$ in Millions
Apr. 18, 2018
USD ($)
Mar. 28, 2018
USD ($)
Nov. 22, 2017
USD ($)
Nov. 01, 2017
USD ($)
Apr. 19, 2017
USD ($)
Mar. 31, 2018
USD ($)
Jul. 31, 2017
USD ($)
certificate
MW
DTE Electric | MPSC              
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
DTE Electric | MPSC | Electric Rate Case Filing 2017              
Public Utilities, General Disclosures [Line Items]              
Requested rate increase       $ 125.0 $ 231.0    
Return on equity percent         10.10%    
Return on equity requested percent         10.50%    
DTE Electric | MPSC | Electric Rate Case Filing 2017 | Refundable self-implemented rates              
Public Utilities, General Disclosures [Line Items]              
Regulatory liabilities           $ 25.0  
DTE Gas              
Public Utilities, General Disclosures [Line Items]              
Reduction of revenue due to Tax Cuts and Jobs Act   $ 38.2          
DTE Gas | MPSC | DTE Gas Rate Case Filing 2017              
Public Utilities, General Disclosures [Line Items]              
Requested rate increase     $ 85.1        
Return on equity percent     10.10%        
Return on equity requested percent     10.50%        
Subsequent event | DTE Electric | MPSC | Electric Rate Case Filing 2017              
Public Utilities, General Disclosures [Line Items]              
Return on equity percent 10.00%            
Approved rate increase $ 65.2