Regulatory Matters	3 Months Ended
Mar. 31, 2017
Public Utilities, General Disclosures [Abstract]
Regulatory Matters	REGULATORY MATTERS 2016 Electric Rate Case Filing DTE Electric filed a rate case with the MPSC on February 1, 2016 requesting an increase in base rates of $344 million based on a projected twelve-month period ending July 31, 2017. On August 1, 2016, DTE Electric self-implemented a base rate increase of $245 million. On January 31, 2017, the MPSC issued an order approving an annual revenue increase of $184 million for service rendered on or after February 7, 2017. The MPSC authorized a return on equity of 10.1%. DTE Electric has recorded a refund liability of $37 million, representing the total estimated refund due to customers, inclusive of interest, at March 31, 2017. DTE Electric will file a self-implementation reconciliation with the MPSC by April 30, 2017. 2017 Electric Rate Case Filing DTE Electric filed a rate case with the MPSC on April 19, 2017 requesting an increase in base rates of $231 million based on a projected twelve-month period ending October 31, 2018. The requested increase in base rates is due primarily to an increase in net plant resulting from infrastructure investments, environmental compliance, and reliability improvement projects. The rate filing also includes projected changes in sales, operation and maintenance expenses, and working capital. The rate filing also requests an increase in return on equity from 10.1% to 10.5% on capital structure. DTE Electric anticipates self-implementing a rate increase in November 2017 with an MPSC order expected by April 2018. 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, NOx and SO₂ emission allowances costs, urea costs, transmission costs, MISO, and other related costs. The MPSC reviews these costs, policies, and practices for prudence in annual plan and reconciliation filings. 2015 PSCR Year — In March 2016, DTE Electric filed its 2015 PSCR reconciliation. The Administrative Law Judge and certain intervenors in the reconciliation case have challenged the recovery of approximately $13 million of costs related to a customer settlement. Resolution of this matter is expected in 2017. 2016 DTE Main Electric Depreciation Case Filing DTE Electric filed a depreciation case with the MPSC on November 1, 2016 requesting an increase in depreciation rates of $156 million when compared to current depreciation rates for Plant in service balances as of December 31, 2015. An MPSC order in this case is expected in 2018.

REGULATORY MATTERS

2016 Electric Rate Case Filing

DTE Electric filed a rate case with the MPSC on February 1, 2016 requesting an increase in base rates of $344 million based on a projected twelve-month period ending July 31, 2017. On August 1, 2016, DTE Electric self-implemented a base rate increase of $245 million. On January 31, 2017, the MPSC issued an order approving an annual revenue increase of $184 million for service rendered on or after February 7, 2017. The MPSC authorized a return on equity of 10.1%. DTE Electric has recorded a refund liability of $37 million, representing the total estimated refund due to customers, inclusive of interest, at March 31, 2017. DTE Electric will file a self-implementation reconciliation with the MPSC by April 30, 2017.

2017 Electric Rate Case Filing

DTE Electric filed a rate case with the MPSC on April 19, 2017 requesting an increase in base rates of $231 million based on a projected twelve-month period ending October 31, 2018. The requested increase in base rates is due primarily to an increase in net plant resulting from infrastructure investments, environmental compliance, and reliability improvement projects. The rate filing also includes projected changes in sales, operation and maintenance expenses, and working capital. The rate filing also requests an increase in return on equity from 10.1% to 10.5% on capital structure. DTE Electric anticipates self-implementing a rate increase in November 2017 with an MPSC order expected by April 2018.

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, NOx and SO₂ emission allowances costs, urea costs, transmission costs, MISO, and other related costs. The MPSC reviews these costs, policies, and practices for prudence in annual plan and reconciliation filings.

2015 PSCR Year — In March 2016, DTE Electric filed its 2015 PSCR reconciliation. The Administrative Law Judge and certain intervenors in the reconciliation case have challenged the recovery of approximately $13 million of costs related to a customer settlement. Resolution of this matter is expected in 2017.

2016 DTE Main Electric Depreciation Case Filing

DTE Electric filed a depreciation case with the MPSC on November 1, 2016 requesting an increase in depreciation rates of $156 million when compared to current depreciation rates for Plant in service balances as of December 31, 2015. An MPSC order in this case is expected in 2018.