Short-Term Credit Arrangements and Borrowings (Details) $ in Millions	Sep. 30, 2021 USD ($)
Availability under combined facilities
Maximum borrowing capacity	$ 2,657
Amounts outstanding	629
Net availability	2,028
DTE Electric
Availability under combined facilities
Maximum borrowing capacity	500
Amounts outstanding	159
Net availability	341
DTE Gas
Availability under combined facilities
Maximum borrowing capacity	300
Amounts outstanding	128
Net availability	172
DTE Energy
Availability under combined facilities
Maximum borrowing capacity	1,857
Amounts outstanding	342
Net availability	1,515
Revolver borrowings
Availability under combined facilities
Amounts outstanding	74
Revolver borrowings | DTE Electric
Availability under combined facilities
Amounts outstanding	0
Revolver borrowings | DTE Gas
Availability under combined facilities
Amounts outstanding	0
Revolver borrowings | DTE Energy
Availability under combined facilities
Amounts outstanding	74
Commercial paper issuances
Availability under combined facilities
Amounts outstanding	287
Commercial paper issuances | DTE Electric
Availability under combined facilities
Amounts outstanding	159
Commercial paper issuances | DTE Gas
Availability under combined facilities
Amounts outstanding	128
Commercial paper issuances | DTE Energy
Availability under combined facilities
Amounts outstanding	0
Letters of credit
Availability under combined facilities
Amounts outstanding	268
Letters of credit | DTE Electric
Availability under combined facilities
Amounts outstanding	0
Letters of credit | DTE Gas
Availability under combined facilities
Amounts outstanding	0
Letters of credit | DTE Energy
Availability under combined facilities
Amounts outstanding	268
Unsecured revolving credit facility, expiring April 2025 | Revolver borrowings
Availability under combined facilities
Maximum borrowing capacity	2,300
Unsecured revolving credit facility, expiring April 2025 | Revolver borrowings | DTE Electric
Availability under combined facilities
Maximum borrowing capacity	500
Unsecured revolving credit facility, expiring April 2025 | Revolver borrowings | DTE Gas
Availability under combined facilities
Maximum borrowing capacity	300
Unsecured revolving credit facility, expiring April 2025 | Revolver borrowings | DTE Energy
Availability under combined facilities
Maximum borrowing capacity	1,500
Unsecured Canadian revolving credit facility, expiring May 2023 | Revolver borrowings
Availability under combined facilities
Maximum borrowing capacity	87
Unsecured Canadian revolving credit facility, expiring May 2023 | Revolver borrowings | DTE Electric
Availability under combined facilities
Maximum borrowing capacity	0
Unsecured Canadian revolving credit facility, expiring May 2023 | Revolver borrowings | DTE Gas
Availability under combined facilities
Maximum borrowing capacity	0
Unsecured Canadian revolving credit facility, expiring May 2023 | Revolver borrowings | DTE Energy
Availability under combined facilities
Maximum borrowing capacity	87
Unsecured letter of credit facility, expiring in February 2023 | Letters of credit
Availability under combined facilities
Maximum borrowing capacity	150
Unsecured letter of credit facility, expiring in February 2023 | Letters of credit | DTE Electric
Availability under combined facilities
Maximum borrowing capacity	0
Unsecured letter of credit facility, expiring in February 2023 | Letters of credit | DTE Gas
Availability under combined facilities
Maximum borrowing capacity	0
Unsecured letter of credit facility, expiring in February 2023 | Letters of credit | DTE Energy
Availability under combined facilities
Maximum borrowing capacity	150
Unsecured letter of credit facility, expiring in July 2023 | Letters of credit
Availability under combined facilities
Maximum borrowing capacity	70
Unsecured letter of credit facility, expiring in July 2023 | Letters of credit | DTE Electric
Availability under combined facilities
Maximum borrowing capacity	0
Unsecured letter of credit facility, expiring in July 2023 | Letters of credit | DTE Gas
Availability under combined facilities
Maximum borrowing capacity	0
Unsecured letter of credit facility, expiring in July 2023 | Letters of credit | DTE Energy
Availability under combined facilities
Maximum borrowing capacity	70
Unsecured letter of credit facility | Letters of credit
Availability under combined facilities
Maximum borrowing capacity	50
Unsecured letter of credit facility | Letters of credit | DTE Electric
Availability under combined facilities
Maximum borrowing capacity	0
Unsecured letter of credit facility | Letters of credit | DTE Gas
Availability under combined facilities
Maximum borrowing capacity	0
Unsecured letter of credit facility | Letters of credit | DTE Energy
Availability under combined facilities
Maximum borrowing capacity	50
Unsecured revolving credit facility, expiring April 2024 | Revolver borrowings
Availability under combined facilities
Maximum borrowing capacity	102
Unsecured revolving credit facility, expiring April 2024 | Revolver borrowings | DTE Electric
Availability under combined facilities
Maximum borrowing capacity	22
Unsecured revolving credit facility, expiring April 2024 | Revolver borrowings | DTE Gas
Availability under combined facilities
Maximum borrowing capacity	13
Unsecured revolving credit facility, expiring April 2024 | Revolver borrowings | DTE Energy
Availability under combined facilities
Maximum borrowing capacity	$ 67