Financial and Other Derivative Instruments (Details 4)	Jun. 30, 2013 dte.volumes
Natural Gas [Member]
Derivative [Line Items]
Volume of Commodity Contracts	574,820,998
Electricity [Member]
Derivative [Line Items]
Volume of Commodity Contracts	64,291,746
Foreign currency exchange contracts [Member]
Derivative [Line Items]
Volume of Commodity Contracts	34,772,009
FTR [Member]
Derivative [Line Items]
Volume of Commodity Contracts	16,224,782