Segment Information (Tables)

12 Months Ended

Dec. 31, 2012

Segment Reporting [Abstract]

Inter segment billing for goods and services [Table Text Block]

	2012			2011			2010
	(In millions)
Electric	$	29		$	33		$	30
Gas	4			2			—
Gas Storage and Pipelines	6			8			4
Power and Industrial Projects	801			238			161
Energy Trading	43			70			89
Corporate and Other	(37		)	(50		)	(65		)
Discontinued Operations	2			—			—
	$	848		$	301		$	219

Schedule of Segment Reporting Information, by Segment [Table Text Block]

Financial data of the business segments follows:

	Operating Revenue			Depreciation, Depletion & Amortization		Interest Income			Interest Expense			Income Taxes			Net Income Attributable to DTE Energy Company			Total Assets			Goodwill		Capital Expenditures
	(In millions)
2012
Electric	$	5,293		$	827	$	(1	)	$	272		$	280		$	483		$	17,755		$	1,208	$	1,230
Gas	1,315			92		(7		)	59			50			115			4,059			745		220
Gas Storage and Pipelines	96			8		(8		)	8			39			61			668			22		233
Power and Industrial Projects	1,823			65		(7		)	37			(44		)	42			991			26		83
Energy Trading	1,109			2		—			8			7			12			629			17		1
Corporate and Other	3			1		(52		)	121			(46		)	(47		)	3,074			—		3
Reclassifications and Eliminations	(848		)	—		65			(65		)	—			—			(837		)	—		—
Total from Continuing Operations	$	8,791		$	995	$	(10	)	$	440		$	286		666			26,339			2,018		1,770
Discontinued Operations (Note 7)															(56		)	—			—		49
Total															$	610		$	26,339		$	2,018	$	1,819

	Operating Revenue			Depreciation, Depletion & Amortization		Interest Income			Interest Expense			Income Taxes			Net Income Attributable to DTE Energy Company			Total Assets			Goodwill		Capital Expenditures
	(In millions)
2011
Electric	$	5,154		$	818	$	(1	)	$	289		$	265		$	434		$	17,567		$	1,208	$	1,203
Gas	1,505			89		(7		)	64			60			110			4,065			745		179
Gas Storage and Pipelines	91			6		(5		)	7			35			57			538			22		16
Power and Industrial Projects	1,129			60		(8		)	32			11			38			789			26		56
Energy Trading	1,276			3		—			9			34			52			612			17		1
Corporate and Other	4			1		(47		)	145			(136		)	23			2,605			—		—
Reclassifications and Eliminations	(301		)	—		58			(58		)	(1		)	—			(485		)	—		—
Total from Continuing Operations	$	8,858		$	977	$	(10	)	$	488		$	268		$	714		$	25,691		$	2,018	$	1,455
Discontinued Operations (Note 7)															(3		)	318			2		29
Total															$	711		$	26,009		$	2,020	$	1,484

	Operating Revenue			Depreciation, Depletion & Amortization		Interest Income			Interest Expense			Income Taxes			Net Income Attributable to DTE Energy Company			Total Assets			Goodwill		Capital Expenditures
	(In millions)
2010
Electric	$	4,993		$	849	$	(1	)	$	313		$	270		$	441		$	16,611		$	1,206	$	864
Gas	1,648			92		(9		)	66			67			127			3,925			759		147
Gas Storage and Pipelines	83			5		(1		)	6			32			51			446			9		5
Power and Industrial Projects	1,144			60		(3		)	33			3			85			872			27		53
Energy Trading	875			5		—			13			5			6			513			17		1
Corporate & Other	1			1		(47		)	160			(62		)	(72		)	2,616			—		—
Reclassifications and Eliminations	(219		)	—		49			(48		)	—			—			(413		)	—		—
Total from Continuing Operations	$	8,525		$	1,012	$	(12	)	$	543		$	315		$	638		$	24,570		$	2,018	$	1,070
Discontinued Operations (Note 7)															(8		)	326			2		27
Total															$	630		$	24,896		$	2,020	$	1,097