Leases (Finance Leases Reported on Consolidated Statements of Financial Position) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Lessee, Lease, Description [Line Items]
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]	Property, Plant and Equipment, Net	Property, Plant and Equipment, Net
Right-of-use assets, within Property, plant, and equipment, net	$ 26	$ 29
Finance Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Long-term Debt and Lease Obligation, Current	Long-term Debt and Lease Obligation, Current
Current lease liabilities, within Current portion of long-term debt	$ 8	$ 7
Long-term lease liabilities	$ 19	$ 24
DTE Electric
Lessee, Lease, Description [Line Items]
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]	Property, Plant and Equipment, Net	Property, Plant and Equipment, Net
Right-of-use assets, within Property, plant, and equipment, net	$ 12	$ 16
Finance Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Long-term Debt and Lease Obligation, Current	Long-term Debt and Lease Obligation, Current
Current lease liabilities, within Current portion of long-term debt	$ 6	$ 6
Long-term lease liabilities	$ 7	$ 13