Earnings Per Share (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Basic Earnings per Share
Net Income Attributable to DTE Energy Company	$ 326	$ 234
Average number of common shares outstanding	177	173
Weighted average net restricted shares outstanding	0	1
Dividends declared on common stock	116	107
Dividends declared - net restricted shares	0	1
Total distributed earnings	116	108
Net income less distributed earnings	210	126
Distributed (dividends per common share)	$ 0.66	$ 0.62
Undistributed	$ 1.18	$ 0.73
Total Basic Earnings per Common Share	$ 1.84	$ 1.35
Diluted Earnings per Share
Net Income Attributable to DTE Energy Company	326	234
Common shares for dilutive calculation	177	173
Weighted average net restricted shares outstanding	0	1
Dividends declared on common stock	116	107
Dividends declared - net restricted shares	0	1
Total distributed earnings	116	108
Net income less distributed earnings	$ 210	$ 126
Distributed (dividends per common share)	$ 0.66	$ 0.62
Undistributed	$ 1.18	$ 0.72
Total Diluted Earnings per Common Share	$ 1.84	$ 1.34