Fair Value (Carrying Amount of Fair Value of Financial Instruments) (Details) - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
Carrying amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes receivable	$ 1,513	$ 1,453
Short-term borrowings	0	882
Notes payable	22	28
Long-term debt	26,695	25,123
Carrying amount | DTE Electric
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes receivable	289	274
Short-term borrowings	0	652
Notes payable	16	24
Long-term debt	14,733	13,165
Carrying amount | DTE Electric | Affiliates
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes receivable	228	0
Fair Value | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes receivable	0	0
Short-term borrowings	0	0
Notes payable	0	0
Long-term debt	1,234	1,285
Fair Value | Level 1 | DTE Electric
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes receivable	0	0
Short-term borrowings	0	0
Notes payable	0	0
Long-term debt	0	0
Fair Value | Level 1 | DTE Electric | Affiliates
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes receivable	0	0
Fair Value | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes receivable	0	0
Short-term borrowings	0	882
Notes payable	0	0
Long-term debt	22,634	21,204
Fair Value | Level 2 | DTE Electric
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes receivable	0	0
Short-term borrowings	0	652
Notes payable	0	0
Long-term debt	13,420	12,048
Fair Value | Level 2 | DTE Electric | Affiliates
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes receivable	0	0
Fair Value | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes receivable	1,500	1,482
Short-term borrowings	0	0
Notes payable	22	28
Long-term debt	1,225	1,351
Fair Value | Level 3 | DTE Electric
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes receivable	309	289
Short-term borrowings	0	0
Notes payable	16	24
Long-term debt	131	131
Fair Value | Level 3 | DTE Electric | Affiliates
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes receivable	$ 228	$ 0