Dispositions and Impairments (Major Classes of Assets and Liabilities Transferred and Presented as Discontinued Operations) (Details) - USD ($)	Sep. 30, 2021	Dec. 31, 2020
Total Assets of Discontinued Operations
Current assets of discontinued operations for DTE Energy	$ 0	$ 217,000,000
Noncurrent assets of discontinued operations for DTE Energy	0	7,859,000,000
Total Liabilities of Discontinued Operations
Current liabilities of discontinued operations for DTE Energy	0	99,000,000
Noncurrent liabilities of discontinued operations for DTE Energy	0	836,000,000
Discontinued operations, spinoff | DT Midstream
Discontinued Operations and Disposal Groups [Abstract]
Cash		42,000,000
Total Assets of Discontinued Operations
Cash		42,000,000
Accounts receivable		126,000,000
Inventories		8,000,000
Other		44,000,000
Current assets of DT Midstream		220,000,000
Less: Previously affiliated amounts eliminated at DTE Energy		3,000,000
Current assets of discontinued operations for DTE Energy		217,000,000
Investments in equity method investees		1,691,000,000
Net property, plant, and equipment		3,470,000,000
Goodwill		473,000,000
Intangible assets		2,140,000,000
Notes receivable		19,000,000
Operating lease right-of-use assets		45,000,000
Other		21,000,000
Noncurrent assets of discontinued operations for DTE Energy		7,859,000,000
Total Assets of Discontinued Operations for DTE Energy	0	8,076,000,000
Total Liabilities of Discontinued Operations
Accounts payable		39,000,000
Operating lease liabilities		17,000,000
Short-term borrowings due to DTE Energy		2,913,000,000
Other		53,000,000
Current liabilities of DT Midstream		3,022,000,000
Less: Previously affiliated amounts eliminated at DTE Energy		2,923,000,000
Current liabilities of discontinued operations for DTE Energy		99,000,000
Deferred income taxes		753,000,000
Asset retirement obligations		10,000,000
Operating lease liabilities		28,000,000
Other		45,000,000
Noncurrent liabilities of discontinued operations for DTE Energy		836,000,000
Total Liabilities of Discontinued Operations for DTE Energy	$ 0	$ 935,000,000