Short-Term Credit Arrangements and Borrowings (Details Textuals)	Sep. 30, 2018 USD ($)	Dec. 31, 2017 USD ($)
Short-term Debt [Line Items]
Other outstanding letters of credit	$ 236,000,000
Letter of credit
Short-term Debt [Line Items]
Other outstanding letters of credit	$ 159,000,000
DTE Electric
Short-term Debt [Line Items]
Ratio of indebtedness to net capital	0.51
Other outstanding letters of credit	$ 51,000,000
DTE Electric | Letter of credit
Short-term Debt [Line Items]
Other outstanding letters of credit	$ 0
DTE Gas
Short-term Debt [Line Items]
Ratio of indebtedness to net capital	0.50
Other outstanding letters of credit	$ 26,000,000
DTE Gas | Letter of credit
Short-term Debt [Line Items]
Other outstanding letters of credit	$ 0
DTE Energy
Short-term Debt [Line Items]
Ratio of indebtedness to net capital	0.54
Other outstanding letters of credit	$ 159,000,000
DTE Energy | Letter of credit
Short-term Debt [Line Items]
Other outstanding letters of credit	159,000,000
DTE Energy | Demand financing agreement
Short-term Debt [Line Items]
Maximum borrowing capacity, financing agreement	100,000,000
Maximum additional margin financing	50,000,000
Amount outstanding	6,000,000	$ 56,000,000
DTE Energy | Demand financing agreement plus letter of credit
Short-term Debt [Line Items]
Maximum borrowing capacity, financing agreement	125,000,000
DTE Energy | Other outstanding letters of credit | Letter of credit
Short-term Debt [Line Items]
Other outstanding letters of credit	$ 9,000,000
Maximum
Short-term Debt [Line Items]
Ratio of indebtedness to net capital	0.65