Fair Value (Details Textuals) (USD $)	12 Months Ended
	Dec. 31, 2012 dte_instances	Dec. 31, 2011	Dec. 31, 2010
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair Value of Cash Equivalents Included in Restricted Cash	$ 109,000,000	$ 124,000,000
Fair Value of Cash Equivalents Included in Other Investments	14,000,000	16,000,000
Other investments	110,000,000	95,000,000
Maturity in Years for Cash and Cash Equivalents	3 months
Number of Certain Forward Market and Basis Prices Used	2
Average Maturity of Debt Securities	6 years	7 years
Unrealized losses recognized as regulatory assets	44,000,000	67,000,000
Fermi I Corresponding Regulatory Asset Treatment	0
Other than Temporary Impairment Losses, Investments, Portion Recognized in Earnings, Net	0	0	0
Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, before Tax	0
Trading Securities, Change in Unrealized Holding Gain (Loss)	9,000,000	3,000,000	7,000,000
Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, before Tax		0
Publicly Traded Equity Securities [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Nuclear Decommissioning Trust Fund Investments	61.00%	57.00%
Fixed Income Securities [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Nuclear Decommissioning Trust Fund Investments	38.00%	41.00%
Cash Equivalents [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Available-for-sale Securities, Fair Value Disclosure	123,000,000	140,000,000
Nuclear Decommissioning Trust Fund Investments	1.00%	2.00%
Equity [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Available-for-sale Securities, Fair Value Disclosure	$ 5,000,000	$ 5,000,000