Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Basic Earnings per Share
Net Income Attributable to DTE Energy Company/DTE Electric	$ 109	$ 124	$ 382	$ 450
Average number of common shares outstanding (in shares)	179	177	179	177
Dividends declared — common shares	$ 124	$ 116	$ 247	$ 231
Dividends declared — net restricted shares	0	0	1	1
Total distributed earnings	124	116	248	232
Net income less distributed earnings	$ (15)	$ 8	$ 134	$ 218
Distributed (dividends per common share) (dollars per share)	$ 0.69	$ 0.66	$ 1.38	$ 1.31
Undistributed (in dollars per share)	(0.08)	0.04	0.75	1.23
Total Basic Earnings per Common Share (dollars per share)	$ 0.61	$ 0.70	$ 2.13	$ 2.54
Diluted Earnings per Share
Net Income Attributable to DTE Energy Company/DTE Electric	$ 109	$ 124	$ 382	$ 450
Average number of common shares outstanding (in shares)	179	177	179	177
Dividends declared — common shares	$ 124	$ 116	$ 247	$ 231
Dividends declared — net restricted shares	0	0	1	1
Total distributed earnings	124	116	248	232
Net income less distributed earnings	$ (15)	$ 8	$ 134	$ 218
Distributed (dividends per common share) (dollars per share)	$ 0.69	$ 0.66	$ 1.38	$ 1.31
Undistributed (dollars per share)	(0.08)	0.04	0.75	1.23
Total Diluted Earnings per Common Share (dollars per share)	$ 0.61	$ 0.70	$ 2.13	$ 2.54