Earnings Per Share (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Basic Earnings per Share
Net Income Attributable to DTE Energy Company	$ 146	$ 202	$ 302	$ 378
Average number of common shares outstanding	170	169	170	169
Weighted average net restricted shares outstanding	1	1	1	1
Dividends declared - common shares	100	99	200	194
Dividends declared - net restricted shares	1	0	1	0
Total distributed earnings	101	99	201	194
Net income less distributed earnings	45	103	101	184
Distributed (dividends per common share)	$ 0.59	$ 0.59	$ 1.18	$ 1.15
Undistributed	$ 0.27	$ 0.60	$ 0.59	$ 1.08
Total Basic Earnings per Common Share	$ 0.86	$ 1.19	$ 1.77	$ 2.23
Diluted Earnings per Share
Net Income Attributable to DTE Energy Company	146	202	302	378
Average number of common shares outstanding	170	169	170	169
Average number of common shares Outstanding 1		170		170
Average incremental shares from assumed exercise of options	1	0	1	0
Common shares for dilutive calculation	171	170	171	170
Weighted average net restricted shares outstanding	1	1	1	1
Dividends declared - common shares	100	99	200	194
Dividends declared - net restricted shares	1	0	1	0
Total distributed earnings	101	99	201	194
Net income less distributed earnings	$ 45	$ 103	$ 101	$ 184
Distributed (dividends per common share)	$ 0.59	$ 0.59	$ 1.18	$ 1.15
Earnings Per Share, Diluted, Undistributed	$ 0.27	$ 0.60	$ 0.59	$ 1.08
Total Diluted Earnings per Common Share	$ 0.86	$ 1.19	$ 1.77	$ 2.23