Supplementary Quarterly Financial Information (Unaudited ) (Tables)

12 Months Ended

Dec. 31, 2012

Quarterly Financial Information Disclosure [Abstract]

Schedule of Quarterly Financial Information [Table Text Block]

Quarterly earnings per share may not equal full year totals, since quarterly computations are based on weighted average common shares outstanding during each quarter.

	First Quarter		Second Quarter			Third Quarter		Fourth Quarter			Year
	(In millions, except per share amounts)
2012
Operating Revenues	$	2,239	$	2,013		$	2,190	$	2,349		$	8,791
Operating Income	$	312	$	294		$	406	$	267		$	1,279
Net Income Attributable to DTE Energy Company
Continuing Operations	$	156	$	147		$	226	$	137		$	666
Discontinued Operations	—		(1		)	1		(56		)	(56		)
Net Income Attributable to DTE Energy Company	$	156	$	146		$	227	$	81		$	610
Basic Earnings per Share
Continuing Operations	$	0.91	$	0.87		$	1.31	$	0.79		$	3.89
Discontinued Operations	—		(0.01		)	0.01		(0.32		)	(0.33		)
Total	$	0.91	$	0.86		$	1.32	$	0.47		$	3.56
Diluted Earnings per Share
Continuing Operations	$	0.91	$	0.87		$	1.30	$	0.79		$	3.88
Discontinued Operations	—		(0.01		)	0.01		(0.32		)	(0.33		)
Total	$	0.91	$	0.86		$	1.31	$	0.47		$	3.55

2011
Operating Revenues	$	2,423		$	2,018		$	2,254	$	2,163		$	8,858
Operating Income	$	389		$	288		$	398	$	346		$	1,421
Net Income Attributable to DTE Energy Company
Continuing Operations (a)	$	177		$	203		$	183	$	151		$	714
Discontinued Operations	(1		)	(1		)	—		(1		)	(3		)
Net Income Attributable to DTE Energy Company	$	176		$	202		$	183	$	150		$	711
Basic Earnings per Share
Continuing Operations	$	1.05		$	1.19		$	1.08	$	0.88		$	4.21
Discontinued Operations	(0.01		)	—			—		—			(0.02		)
Total	$	1.04		$	1.19		$	1.08	$	0.88		$	4.19
Diluted Earnings per Share
Continuing Operations	$	1.05		$	1.19		$	1.07	$	0.88		$	4.20
Discontinued Operations	(0.01		)	—			—		—			(0.02		)
Total	$	1.04		$	1.19		$	1.07	$	0.88		$	4.18