Regulatory Matters	3 Months Ended
Mar. 31, 2015
Public Utilities, General Disclosures [Abstract]
Regulatory Matters	REGULATORY MATTERS 2014 Electric Rate Case Filing DTE Electric filed a rate case with the MPSC on December 19, 2014 requesting an increase in base rates of $370 million based on a projected twelve-month period ending June 30, 2016. The requested increase in base rates is due primarily to an increase in net plant resulting from infrastructure investments, plant acquisitions, environmental compliance and reliability improvement projects. The rate filing also included projected changes in sales, working capital, operation and maintenance expenses, return on equity and capital structure. New rates could be self-implemented in July 2015, with a final order expected in December 2015. Refundable Revenue Decoupling / Deferred Gain Amortization In September 2012, the MPSC approved DTE Electric's accounting application to defer for future amortization the gain resulting from the reversal of DTE Electric's $127 million regulatory liability associated with the operation of the RDM. The approved application provided for the amortization of the regulatory liability to income, at a monthly rate of approximately $10.6 million, beginning January 2014. On April 1, 2014, the MPSC approved DTE Electric's accounting application to suspend the amortization of the RDM regulatory liability as of June 30, 2014. DTE Electric amortized one-half of the RDM regulatory liability in the first six months of 2014 and resumed amortization of the remainder beginning January 1, 2015. If DTE Electric's base rates are increased prior to July 1, 2015, DTE Electric will cease amortization and refund to customers the remaining unamortized balance of the regulatory liability. PSCR 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 PSCR Year — In March 2013, DTE Electric filed its 2012 PSCR reconciliation that included purchased power costs related to the manual shutdown of the Fermi 2 nuclear power plant in June 2012 caused by the failure of one of the plant's two non-safety related feed-water pumps. The plant was restarted on July 30, 2012, which restored production to approximately 68% of full capacity. In September 2013, the repair to the plant was completed and production was returned to full capacity. DTE Electric was able to purchase sufficient power from MISO to continue to provide uninterrupted service to customers. Certain intervenors in the reconciliation case have challenged the recovery of up to $32 million of the Fermi 2 related purchased power costs. In April 2015, an MPSC Administrative Law Judge issued a Proposal for Decision that challenged the recovery of approximately $50 million of such costs. Resolution of this matter is expected in 2016.

REGULATORY MATTERS

2014 Electric Rate Case Filing

DTE Electric filed a rate case with the MPSC on December 19, 2014 requesting an increase in base rates of $370 million based on a projected twelve-month period ending June 30, 2016. The requested increase in base rates is due primarily to an increase in net plant resulting from infrastructure investments, plant acquisitions, environmental compliance and reliability improvement projects. The rate filing also included projected changes in sales, working capital, operation and maintenance expenses, return on equity and capital structure. New rates could be self-implemented in July 2015, with a final order expected in December 2015.

Refundable Revenue Decoupling / Deferred Gain Amortization

In September 2012, the MPSC approved DTE Electric's accounting application to defer for future amortization the gain resulting from the reversal of DTE Electric's $127 million regulatory liability associated with the operation of the RDM. The approved application provided for the amortization of the regulatory liability to income, at a monthly rate of approximately $10.6 million, beginning January 2014. On April 1, 2014, the MPSC approved DTE Electric's accounting application to suspend the amortization of the RDM regulatory liability as of June 30, 2014. DTE Electric amortized one-half of the RDM regulatory liability in the first six months of 2014 and resumed amortization of the remainder beginning January 1, 2015. If DTE Electric's base rates are increased prior to July 1, 2015, DTE Electric will cease amortization and refund to customers the remaining unamortized balance of the regulatory liability.

PSCR 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 PSCR Year — In March 2013, DTE Electric filed its 2012 PSCR reconciliation that included purchased power costs related to the manual shutdown of the Fermi 2 nuclear power plant in June 2012 caused by the failure of one of the plant's two non-safety related feed-water pumps. The plant was restarted on July 30, 2012, which restored production to approximately 68% of full capacity. In September 2013, the repair to the plant was completed and production was returned to full capacity. DTE Electric was able to purchase sufficient power from MISO to continue to provide uninterrupted service to customers. Certain intervenors in the reconciliation case have challenged the recovery of up to $32 million of the Fermi 2 related purchased power costs. In April 2015, an MPSC Administrative Law Judge issued a Proposal for Decision that challenged the recovery of approximately $50 million of such costs. Resolution of this matter is expected in 2016.