Short-Term Credit Arrangements and Borrowings (Details Textuals) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Jun. 30, 2013 banks	Mar. 31, 2013 banks	Mar. 31, 2013 DTE Electric [Member]	Dec. 31, 2012 DTE Electric [Member]
Short-term Debt [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 300	$ 300
Revolving Credit Facilities with a Syndicate Number of Banks	19	20
Number of Banks that Provide Percentage of Commitment in any Facility	1	1
Maximum Percentage of Commitment to Bank in any Facility	8.70%	8.50%
Time Period of Amended and Restated Credit Agreement	5 years
Long-term Commercial Paper, Current			$ 0	$ 130
Maximum Total Funded Debt to Total Capitalization Ratio		0.65
Maximum Total Funded Debt to Total Capitilization Ration Denominator		1
Total Funded Debt to Total Capitalization Ratio		0.53
Total Funded Debt to Total Capitalization Ratio Denominator		1