Short-Term Credit Arrangements and Borrowings (Details)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Short-term Debt [Line Items]
Other outstanding letters of credit	$ 745,000,000
Weighted average interest rate	1.90%	0.90%
Dividend restriction	$ 1,800,000,000
Retained earnings	5,643,000,000	$ 5,114,000,000
Effective limitations	$ 0
Maximum
Short-term Debt [Line Items]
Total funded debt to capitalization ratio	0.65
Letters of credit
Short-term Debt [Line Items]
Other outstanding letters of credit	$ 124,000,000
DTE Electric
Short-term Debt [Line Items]
Total funded debt to capitalization ratio	0.50
Other outstanding letters of credit	$ 238,000,000
Weighted average interest rate	1.50%	0.80%
Retained earnings	$ 1,956,000,000	$ 1,787,000,000
DTE Electric | Letters of credit
Short-term Debt [Line Items]
Other outstanding letters of credit	$ 0
DTE Gas
Short-term Debt [Line Items]
Total funded debt to capitalization ratio	0.48
Other outstanding letters of credit	$ 300,000,000
DTE Gas | Letters of credit
Short-term Debt [Line Items]
Other outstanding letters of credit	$ 0
DTE Energy
Short-term Debt [Line Items]
Total funded debt to capitalization ratio	0.54
Other outstanding letters of credit	$ 207,000,000
DTE Energy | Letters of credit
Short-term Debt [Line Items]
Other outstanding letters of credit	124,000,000
DTE Energy | Demand financing agreement
Short-term Debt [Line Items]
Maximum borrowing capacity	100,000,000
Additional margin financing	50,000,000
Amount outstanding	56,000,000	$ 50,000,000
DTE Energy | Demand financing agreement plus letter of credit
Short-term Debt [Line Items]
Maximum borrowing capacity	100,000,000
DTE Energy | Other outstanding letters of credit | Letters of credit
Short-term Debt [Line Items]
Other outstanding letters of credit	$ 9,000,000