Regulatory Matters (Notes)	3 Months Ended
Mar. 31, 2013
Public Utilities, General Disclosures [Abstract]
REGULATORY MATTERS	REGULATORY MATTERS DTE Electric Restoration Expense Tracking Mechanism (RETM) and Line Clearance Tracking (LCT) Reconciliation In January 2012, DTE Electric filed an application with the MPSC for approval of the reconciliation of its 2011 RETM and LCT. The Company's 2011 restoration expenses were higher than the amount provided in rates. Accordingly, DTE Electric requested net recovery of approximately $44 million. On February 28, 2013, the MPSC approved a settlement agreement and authorized a $44 million net surcharge to recover the costs over a three-month period beginning April 1, 2013. DTE Electric Uncollectible Expense True-Up Mechanism (UETM) In February 2012, DTE Electric filed an application with the MPSC for approval of its UETM for 2011 requesting authority to refund approximately $9 million consisting of costs related to 2011 uncollectible expense. On February 28, 2013, the MPSC approved a settlement agreement and authorized a $9 million credit to refund the overrecovery over a one-month period beginning in April 1, 2013. Power Supply Cost Recovery Proceedings The PSCR process is designed to allow DTE Electric to recover all of its power supply costs if incurred under reasonable and prudent policies and practices. DTE Electric's power supply costs include fuel and related transportation costs, purchased and net interchange power costs, nitrogen oxide and sulfur dioxide emission allowances costs, urea costs, transmission costs and MISO costs. The MPSC reviews these costs, policies and practices for prudence in annual plan and reconciliation filings. 2012 Plan Year - In March 2013, DTE Electric filed the 2012 PSCR reconciliation calculating a net under-recovery of approximately $87 million that includes an under-recovery of approximately $148 million for the 2011 PSCR year. 2012 Gas Rate Case Filing DTE Gas filed a rate case on April 20, 2012 based on a projected test year for the twelve-month period ending October 31, 2013. On December 20, 2012, the MPSC approved a partial settlement agreement and authorized the Company to increase its annual gas revenues by $19.9 million for service rendered on and after January 1, 2013. The partial settlement agreement did not resolve the proposal for an infrastructure recovery mechanism (IRM) designed to recover DTE Gas' projected costs over a five-year period related to its gas main renewal, pipeline integrity and meter move out programs. On April 16, 2013, the MPSC issued an order approving the IRM and authorized the recovery of the cost of service related to $77 million of annual investment in the programs beginning in May 2013. The IRM will adjust annually in July for the incremental investment each year, after a limited hearing on the reconciliation of the prior year capital expenditures. If DTE Gas files a rate case during the five-year period, the IRM will be suspended when new rates are set by the MPSC. DTE Gas UETM In March 2013, DTE Gas filed an application with the MPSC for approval of its UETM reconciliation for 2012 requesting authority to refund approximately $20 million. DTE Gas Revenue Decoupling Mechanism (RDM) In October 2012, DTE Gas filed an application with the MPSC for approval of its RDM reconciliation for the period July 1, 2011 through June 30, 2012. The application requests authority to adjust existing retail gas rates so as to collect a net amount of $8.6 million, plus interest. On March 15, 2013, the MPSC approved a settlement agreement and authorized the implementation of surcharges during the billing months of April 2013 through March 2014.

REGULATORY MATTERS

DTE Electric Restoration Expense Tracking Mechanism (RETM) and Line Clearance Tracking (LCT) Reconciliation

In January 2012, DTE Electric filed an application with the MPSC for approval of the reconciliation of its 2011 RETM and LCT. The Company's 2011 restoration expenses were higher than the amount provided in rates. Accordingly, DTE Electric requested net recovery of approximately $44 million. On February 28, 2013, the MPSC approved a settlement agreement and authorized a $44 million net surcharge to recover the costs over a three-month period beginning April 1, 2013.

DTE Electric Uncollectible Expense True-Up Mechanism (UETM)

In February 2012, DTE Electric filed an application with the MPSC for approval of its UETM for 2011 requesting authority to refund approximately $9 million consisting of costs related to 2011 uncollectible expense. On February 28, 2013, the MPSC approved a settlement agreement and authorized a $9 million credit to refund the overrecovery over a one-month period beginning in April 1, 2013.

Power Supply Cost Recovery Proceedings

The PSCR process is designed to allow DTE Electric to recover all of its power supply costs if incurred under reasonable and prudent policies and practices. DTE Electric's power supply costs include fuel and related transportation costs, purchased and net interchange power costs, nitrogen oxide and sulfur dioxide emission allowances costs, urea costs, transmission costs and MISO costs. The MPSC reviews these costs, policies and practices for prudence in annual plan and reconciliation filings.

2012 Plan Year - In March 2013, DTE Electric filed the 2012 PSCR reconciliation calculating a net under-recovery of approximately $87 million that includes an under-recovery of approximately $148 million for the 2011 PSCR year.

2012 Gas Rate Case Filing

DTE Gas filed a rate case on April 20, 2012 based on a projected test year for the twelve-month period ending October 31, 2013. On December 20, 2012, the MPSC approved a partial settlement agreement and authorized the Company to increase its annual gas revenues by $19.9 million for service rendered on and after January 1, 2013. The partial settlement agreement did not resolve the proposal for an infrastructure recovery mechanism (IRM) designed to recover DTE Gas' projected costs over a five-year period related to its gas main renewal, pipeline integrity and meter move out programs. On April 16, 2013, the MPSC issued an order approving the IRM and authorized the recovery of the cost of service related to $77 million of annual investment in the programs beginning in May 2013. The IRM will adjust annually in July for the incremental investment each year, after a limited hearing on the reconciliation of the prior year capital expenditures. If DTE Gas files a rate case during the five-year period, the IRM will be suspended when new rates are set by the MPSC.

DTE Gas UETM

In March 2013, DTE Gas filed an application with the MPSC for approval of its UETM reconciliation for 2012 requesting authority to refund approximately $20 million.

DTE Gas Revenue Decoupling Mechanism (RDM)

In October 2012, DTE Gas filed an application with the MPSC for approval of its RDM reconciliation for the period July 1, 2011 through June 30, 2012. The application requests authority to adjust existing retail gas rates so as to collect a net amount of $8.6 million, plus interest. On March 15, 2013, the MPSC approved a settlement agreement and authorized the implementation of surcharges during the billing months of April 2013 through March 2014.