Supplementary Quarterly Financial Information (Unaudited) (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Quarterly Information [Line Items]
Operating Revenues	$ 2,349	$ 2,190	$ 2,013	$ 2,239	$ 2,163	$ 2,254	$ 2,018	$ 2,423	$ 8,791	$ 8,858	$ 8,525
Operating Income (Loss)	267	406	294	312	346	398	288	389	1,279	1,421	1,470
Income (Loss) from Continuing Operations Attributable to Parent	137	226	147	156	151	183	203	177	666	714
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent	(56.00)	1.00	(1.00)	0	(1.00)	0	(1.00)	(1.00)	(56.00)	(3.00)	(8.00)
Net Income Attributable to DTE Energy Company	81	227	146	156	150	183	202	176	610	711	630
Income (Loss) from Continuing Operations, Per Basic Share	$ 0.79	$ 1.31	$ 0.87	$ 0.91	$ 0.88	$ 1.08	$ 1.19	$ 1.05	$ 3.89	$ 4.21	$ 3.79
Income (Loss) from Discontinued Operations, Net of Tax, Per Basic Share	$ (0.32)	$ 0.01	$ (0.01)	$ 0.00	$ 0.00	$ 0.00	$ 0.00	$ (0.01)	$ (0.33)	$ (0.02)	$ (0.04)
Basic Earnings per Share	$ 0.47	$ 1.32	$ 0.86	$ 0.91	$ 0.88	$ 1.08	$ 1.19	$ 1.04	$ 3.56	$ 4.19	$ 3.75
Income (Loss) from Continuing Operations, Per Diluted Share	$ 0.79	$ 1.30	$ 0.87	$ 0.91	$ 0.88	$ 1.07	$ 1.19	$ 1.05	$ 3.88	$ 4.20	$ 3.78
Income (Loss) from Discontinued Operations, Net of Tax, Per Diluted Share	$ (0.32)	$ 0.01	$ (0.01)	$ 0	$ 0	$ 0	$ 0	$ (0.01)	$ (0.33)	$ (0.02)	$ (0.04)
Diluted Earnings per Share	$ 0	$ 1.31	$ 0.86	$ 0.91	$ 0.88	$ 1.07	$ 1.19	$ 1.04	$ 3.55	$ 4.18	$ 3.74
Income Tax Benefit							$ 87