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Fair Value (Details Textuals) - USD ($)
12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Fair Value, Option, Quantitative Disclosures [Line Items]      
Gains from trading securities $ 15,000,000 $ 1,000,000 $ 14,000,000
Net Unrealized Gain on Investments      
Fair Value, Option, Quantitative Disclosures [Line Items]      
Unrealized losses on available-for-sale securities reclassified out of other comprehensive income (loss) 0 0  
DTE Electric      
Fair Value, Option, Quantitative Disclosures [Line Items]      
Unrealized losses on available-for-sale securities reclassified out of other comprehensive income (loss) 0 0  
Gains from trading securities 15,000,000 1,000,000 $ 14,000,000
DTE Electric | Net Unrealized Gain on Investments      
Fair Value, Option, Quantitative Disclosures [Line Items]      
Unrealized losses on available-for-sale securities reclassified out of other comprehensive income (loss) $ 0 $ 0  
DTE Electric | Nuclear decommissioning trusts      
Fair Value, Option, Quantitative Disclosures [Line Items]      
Average maturity of debt securities 7 years 6 years