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Fair Value (Details Textuals) - USD ($)
3 Months Ended
Mar. 31, 2017
Mar. 31, 2016
Fair Value, Option, Quantitative Disclosures [Line Items]    
Trading securities realized gain (loss) $ 8,000,000 $ 5,000,000
DTE Electric    
Fair Value, Option, Quantitative Disclosures [Line Items]    
Trading securities realized gain (loss) 8,000,000 5,000,000
Accumulated net unrealized investment gain (loss)    
Fair Value, Option, Quantitative Disclosures [Line Items]    
Unrealized losses on available for sale securities 0 0
Accumulated net unrealized investment gain (loss) | DTE Electric    
Fair Value, Option, Quantitative Disclosures [Line Items]    
Unrealized losses on available for sale securities $ 0 $ 0