Consolidated Statements of Operations (Unaudited) (USD $)
In Millions, except Per Share data, unless otherwise specified
 3 Months Ended 9 Months Ended
Sep. 30, 2012
Sep. 30, 2011
Sep. 30, 2012
Sep. 30, 2011
Operating Revenues $ 2,206 $ 2,265 $ 6,480 $ 6,724
Operating Expenses        
Fuel, purchased power and gas 761 866 2,347 2,708
Operation and maintenance 692 670 2,126 1,948
Depreciation, depletion and amortization 265 259 747 752
Taxes other than income 80 79 254 239
Asset (gains) and losses, reserves and impairments, net (2) (8) (10) 0
Total operating expenses 1,796 1,866 5,464 5,647
Operating Income 410 399 1,016 1,077
Other (Income) and Deductions        
Interest expense 112 120 334 370
Interest income (2) (3) (7) (8)
Other income (47) (20) (125) (59)
Other expenses 9 16 28 31
Total Other (Income) and Deductions 72 113 230 334
Income Before Income Taxes 338 286 786 743
Income Tax Expense 108 101 251 180
Net Income 230 185 535 563
Less: Net Income Attributable to Noncontrolling Interests 3 2 6 2
Net Income Attributable to DTE Energy Company $ 227 $ 183 $ 529 $ 561
Basic Earnings per Common Share        
Net Income Attributable to DTE Energy Company $ 1.32 $ 1.08 $ 3.09 $ 3.31
Diluted Earnings per Common Share        
Net Income Attributable to DTE Energy Company $ 1.31 $ 1.07 $ 3.08 $ 3.30
Weighted Average Common Shares Outstanding        
Basic 172 169 171 169
Diluted 172 170 171 170
Dividends Declared per Common Share $ 0.62 $ 0.59 $ 1.80 $ 1.74