Segment and Related Information (Profit (Loss) Financial Data) (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025
Segment Reporting Information [Line Items]
Operating Revenues — Utility operations	$ 2,623	$ 2,307
Operating Revenues — Non-utility operations	2,518	2,133
Depreciation and amortization	483	452
Interest expense	293	250
Interest income	(31)	(23)
Equity earnings of equity method investees	3	7
Other segment items (pre-tax)	4,204	3,327
Income Tax Expense (Benefit)	(58)	(18)
Net Income Attributable to DTE Energy Company	247	445
Other Financial Data
Investments in equity method investees	112		$ 122
Capital expenditures and acquisitions	1,229		4,639
Goodwill	1,993		1,993
Total Assets	55,108		54,066
Operating segments
Segment Reporting Information [Line Items]
Operating Revenues — Utility operations	2,649	2,330
Operating Revenues — Non-utility operations	2,605	2,219
Depreciation and amortization	483	452
Interest expense	195	175
Interest income	(32)	(27)
Equity earnings of equity method investees	3	7
Other segment items (pre-tax)	4,317	3,433
Income Tax Expense (Benefit)	(3)	74
Net Income Attributable to DTE Energy Company	291	435
Other Financial Data
Investments in equity method investees	101		100
Capital expenditures and acquisitions	1,229		4,639
Goodwill	1,993		1,993
Total Assets	53,451		52,096
Operating segments | Electric segment
Segment Reporting Information [Line Items]
Operating Revenues — Utility operations	1,717	1,454
Operating Revenues — Non-utility operations	27	5
Depreciation and amortization	409	382
Interest expense	147	133
Interest income	(3)	(2)
Equity earnings of equity method investees	0	0
Other segment items (pre-tax)	989	826
Income Tax Expense (Benefit)	(16)	(3)
Net Income Attributable to DTE Energy Company	218	123
Other Financial Data
Investments in equity method investees	4		4
Capital expenditures and acquisitions	1,048		3,892
Goodwill	1,208		1,208
Total Assets	40,719		39,370
Operating segments | Gas segment
Segment Reporting Information [Line Items]
Operating Revenues — Utility operations	932	876
Operating Revenues — Non-utility operations	0	0
Depreciation and amortization	58	54
Interest expense	35	32
Interest income	(1)	(2)
Equity earnings of equity method investees	1	0
Other segment items (pre-tax)	566	523
Income Tax Expense (Benefit)	63	63
Net Income Attributable to DTE Energy Company	210	206
Other Financial Data
Investments in equity method investees	19		19
Capital expenditures and acquisitions	166		661
Goodwill	743		743
Total Assets	9,215		8,987
Operating segments | DTE Vantage segment
Segment Reporting Information [Line Items]
Operating Revenues — Utility operations	0	0
Operating Revenues — Non-utility operations	227	188
Depreciation and amortization	15	15
Interest expense	7	8
Interest income	(25)	(20)
Equity earnings of equity method investees	2	7
Other segment items (pre-tax)	311	147
Income Tax Expense (Benefit)	(24)	(8)
Net Income Attributable to DTE Energy Company	(59)	39
Other Financial Data
Investments in equity method investees	78		77
Capital expenditures and acquisitions	14		80
Goodwill	25		25
Total Assets	2,519		2,426
Operating segments | Energy Trading segment
Segment Reporting Information [Line Items]
Operating Revenues — Utility operations	0	0
Operating Revenues — Non-utility operations	2,351	2,026
Depreciation and amortization	1	1
Interest expense	6	2
Interest income	(3)	(3)
Equity earnings of equity method investees	0	0
Other segment items (pre-tax)	2,451	1,937
Income Tax Expense (Benefit)	(26)	22
Net Income Attributable to DTE Energy Company	(78)	67
Other Financial Data
Investments in equity method investees	0		0
Capital expenditures and acquisitions	1		6
Goodwill	17		17
Total Assets	998		1,313
Corporate and Other
Segment Reporting Information [Line Items]
Operating Revenues — Utility operations	0	0
Operating Revenues — Non-utility operations	0	0
Depreciation and amortization	0	0
Interest expense	117	94
Interest income	(18)	(15)
Equity earnings of equity method investees	0	0
Other segment items (pre-tax)	0	3
Income Tax Expense (Benefit)	(55)	(92)
Net Income Attributable to DTE Energy Company	(44)	10
Other Financial Data
Investments in equity method investees	11		22
Capital expenditures and acquisitions	0		0
Goodwill	0		0
Total Assets	5,270		5,145
Reclassifications and Eliminations
Segment Reporting Information [Line Items]
Operating Revenues — Utility operations	(26)	(23)
Operating Revenues — Non-utility operations	(87)	(86)
Depreciation and amortization	0	0
Interest expense	(19)	(19)
Interest income	19	19
Equity earnings of equity method investees	0	0
Other segment items (pre-tax)	(113)	(109)
Income Tax Expense (Benefit)	0	0
Net Income Attributable to DTE Energy Company	0	0
Other Financial Data
Investments in equity method investees	0		0
Capital expenditures and acquisitions	0		0
Goodwill	0		0
Total Assets	(3,613)		$ (3,175)
Reclassifications and Eliminations | Electric segment
Segment Reporting Information [Line Items]
Operating Revenues — Non-utility operations	$ (1)	$ (1)