Short-Term Credit Arrangements and Borrowings (Details) (USD $)	Mar. 31, 2015
Availability under combined facilities
Maximum borrowing capacity	$ 2,025,000,000
Amounts outstanding	255,000,000us-gaap_LineOfCredit
Net availability	1,770,000,000
DTE Energy
Availability under combined facilities
Maximum borrowing capacity	1,425,000,000
Amounts outstanding	255,000,000
Net availability	1,170,000,000
DTE Electric
Availability under combined facilities
Maximum borrowing capacity	300,000,000
Amounts outstanding	0
Net availability	300,000,000
DTE Gas
Availability under combined facilities
Maximum borrowing capacity	300,000,000
Amounts outstanding	0
Net availability	300,000,000
Letter of Credit
Availability under combined facilities
Amounts outstanding	255,000,000
Letter of Credit \| DTE Energy
Availability under combined facilities
Amounts outstanding	255,000,000
Letter of Credit \| DTE Electric
Availability under combined facilities
Amounts outstanding	0
Letter of Credit \| DTE Gas
Availability under combined facilities
Amounts outstanding	0
Letter of Credit \| Unsecured letter of credit facility, expiring in February 2017
Availability under combined facilities
Maximum borrowing capacity	100,000,000
Letter of Credit \| Unsecured letter of credit facility, expiring in February 2017 \| DTE Energy
Availability under combined facilities
Maximum borrowing capacity	100,000,000
Letter of Credit \| Unsecured letter of credit facility, expiring in February 2017 \| DTE Electric
Availability under combined facilities
Maximum borrowing capacity	0
Letter of Credit \| Unsecured letter of credit facility, expiring in February 2017 \| DTE Gas
Availability under combined facilities
Maximum borrowing capacity	0
Letter of Credit \| Unsecured letter of credit facility, expiring in August 2015
Availability under combined facilities
Maximum borrowing capacity	125,000,000
Letter of Credit \| Unsecured letter of credit facility, expiring in August 2015 \| DTE Energy
Availability under combined facilities
Maximum borrowing capacity	125,000,000
Letter of Credit \| Unsecured letter of credit facility, expiring in August 2015 \| DTE Electric
Availability under combined facilities
Maximum borrowing capacity	0
Letter of Credit \| Unsecured letter of credit facility, expiring in August 2015 \| DTE Gas
Availability under combined facilities
Maximum borrowing capacity	0
Revolving Credit Facility \| Unsecured revolving credit facility, expiring April 2018
Availability under combined facilities
Maximum borrowing capacity	1,800,000,000
Revolving Credit Facility \| Unsecured revolving credit facility, expiring April 2018 \| DTE Energy
Availability under combined facilities
Maximum borrowing capacity	1,200,000,000
Revolving Credit Facility \| Unsecured revolving credit facility, expiring April 2018 \| DTE Electric
Availability under combined facilities
Maximum borrowing capacity	300,000,000
Revolving Credit Facility \| Unsecured revolving credit facility, expiring April 2018 \| DTE Gas
Availability under combined facilities
Maximum borrowing capacity	$ 300,000,000

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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