Earnings Per Share (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Basic Earnings per Share
Net Income Attributable to DTE Energy Company	$ 105	$ 146	$ 339	$ 302
Average number of common shares outstanding	174	170	174	170
Weighted average net restricted shares outstanding	1	1	1	1
Dividends declared - common shares	114	100	222	200
Dividends declared - net restricted shares	1	1	0	1
Total distributed earnings	115	101	222	201
Net income less distributed earnings	(10)	45	117	101
Distributed (dividends per common share)	$ 0.66	$ 0.59	$ 1.28	$ 1.18
Undistributed	$ (0.06)	$ 0.27	$ 0.66	$ 0.59
Total Basic Earnings per Common Share	$ 0.60	$ 0.86	$ 1.94	$ 1.77
Diluted Earnings per Share
Net Income Attributable to DTE Energy Company	105	146	339	302
Average number of common shares outstanding	174	170	174	170
Average incremental shares from assumed exercise of options	0	1	0	1
Common shares for dilutive calculation	175	171	174	171
Weighted average net restricted shares outstanding	1	1	1	1
Dividends declared - common shares	114	100	222	200
Dividends declared - net restricted shares	1	1	0	1
Total distributed earnings	115	101	222	201
Net income less distributed earnings	$ (10)	$ 45	$ 117	$ 101
Distributed (dividends per common share)	$ 0.66	$ 0.59	$ 1.28	$ 1.18
Undistributed	$ (0.06)	$ 0.27	$ 0.66	$ 0.59
Total Diluted Earnings per Common Share	$ 0.60	$ 0.86	$ 1.94	$ 1.77