Short-Term Credit Arrangements and Borrowings (Details)	Sep. 30, 2015 USD ($)
Availability under combined facilities
Maximum borrowing capacity	$ 2,070,000,000
Amounts outstanding	370,000,000
Net availability	1,700,000,000
DTE Energy
Availability under combined facilities
Maximum borrowing capacity	1,370,000,000
Amounts outstanding	196,000,000
Net availability	1,174,000,000
DTE Electric
Availability under combined facilities
Maximum borrowing capacity	400,000,000
Amounts outstanding	46,000,000
Net availability	354,000,000
DTE Gas
Availability under combined facilities
Maximum borrowing capacity	300,000,000
Amounts outstanding	128,000,000
Net availability	172,000,000
Letter of Credit
Availability under combined facilities
Amounts outstanding	185,000,000
Letter of Credit | DTE Energy
Availability under combined facilities
Amounts outstanding	185,000,000
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 September 2017
Availability under combined facilities
Maximum borrowing capacity	70,000,000
Letter of Credit | Unsecured letter of credit facility, expiring in September 2017 | DTE Energy
Availability under combined facilities
Maximum borrowing capacity	70,000,000
Letter of Credit | Unsecured letter of credit facility, expiring in September 2017 | DTE Electric
Availability under combined facilities
Maximum borrowing capacity	0
Letter of Credit | Unsecured letter of credit facility, expiring in September 2017 | DTE Gas
Availability under combined facilities
Maximum borrowing capacity	0
Revolving Credit Facility | Unsecured revolving credit facility, expiring April 2020
Availability under combined facilities
Maximum borrowing capacity	1,900,000,000
Revolving Credit Facility | Unsecured revolving credit facility, expiring April 2020 | DTE Energy
Availability under combined facilities
Maximum borrowing capacity	1,200,000,000
Revolving Credit Facility | Unsecured revolving credit facility, expiring April 2020 | DTE Electric
Availability under combined facilities
Maximum borrowing capacity	400,000,000
Revolving Credit Facility | Unsecured revolving credit facility, expiring April 2020 | DTE Gas
Availability under combined facilities
Maximum borrowing capacity	300,000,000
Commercial paper issuances
Availability under combined facilities
Amounts outstanding	185,000,000
Commercial paper issuances | DTE Energy
Availability under combined facilities
Amounts outstanding	11,000,000
Commercial paper issuances | DTE Electric
Availability under combined facilities
Amounts outstanding	46,000,000
Commercial paper issuances | DTE Gas
Availability under combined facilities
Amounts outstanding	$ 128,000,000