Financial and Other Derivative Instruments (Cumulative Gross Volume of Derivative Contracts Outstanding) (Details)	Jun. 30, 2014 dte.volumes
Natural Gas Commodity Contract [Member]
Derivative [Line Items]
Volume of Commodity Contracts	815,660,484
Electricity Commodity Contract [Member]
Derivative [Line Items]
Volume of Commodity Contracts	19,527,918
Oil Commodity Contract [Member]
Derivative [Line Items]
Volume of Commodity Contracts	11,592,000
Foreign currency exchange contracts [Member]
Derivative [Line Items]
Volume of Commodity Contracts	79,076,508