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Fair Value (Assets and Liabilities Recorded at Fair Value on a Recurring Basis) (Details) - USD ($)
$ in Millions
Dec. 31, 2015
Dec. 31, 2014
Derivative Asset [Abstract]    
Derivative asset, gross $ 711 $ 1,178
Derivative asset, Netting (528) (1,006)
Derivative assets, net 183 172
Liabilities [Abstract]    
Derivative Liabilities (705) (1,110)
Derivative liability, netting 562 1,025
Derivative Liabilities, net (143) (85)
Current Derivative Liability    
Liabilities [Abstract]    
Derivative Liabilities (521) (1,041)
Noncurrent Derivative Liability    
Liabilities [Abstract]    
Derivative Liabilities (184) (69)
Natural Gas    
Derivative Asset [Abstract]    
Derivative asset, gross 387 787
Derivative asset, Netting (285) (681)
Derivative assets, net 102 106
Liabilities [Abstract]    
Derivative Liabilities (383) (718)
Derivative liability, netting 294 679
Derivative Liabilities, net (89) (39)
Electricity    
Derivative Asset [Abstract]    
Derivative asset, gross 307 342
Derivative asset, Netting (232) (280)
Derivative assets, net 75 62
Liabilities [Abstract]    
Derivative Liabilities (305) (342)
Derivative liability, netting 253 298
Derivative Liabilities, net (52) (44)
Other    
Derivative Asset [Abstract]    
Derivative asset, gross 5 45
Derivative asset, Netting (2) (42)
Derivative assets, net 3 3
Liabilities [Abstract]    
Derivative Liabilities (10) (45)
Derivative liability, netting 8 45
Derivative Liabilities, net (2) 0
Other derivative contracts    
Derivative Asset [Abstract]    
Derivative asset, gross 12 4
Derivative asset, Netting (9) (3)
Derivative assets, net 3 1
Liabilities [Abstract]    
Derivative Liabilities (7) (5)
Derivative liability, netting 7 3
Derivative Liabilities, net 0 (2)
Recurring    
Assets [Abstract]    
Cash equivalents 16 112
Nuclear decommissioning trusts 1,236 1,241
Other Investments 149 150
Derivative Asset [Abstract]    
Derivative asset, Netting (528) (1,006)
Derivative assets, net 183 172
Total assets 1,584 1,675
Liabilities [Abstract]    
Derivative liability, netting 562 1,025
Derivative Liabilities, net (143) (85)
Net Assets (Liabilities) at the end of the period 1,441 1,590
Net Assets (Liabilities) at the end of the period, netting 34 19
Recurring | Current Asset    
Derivative Asset [Abstract]    
Derivative asset, Netting (441) (955)
Total assets 145 240
Recurring | Noncurrent Asset    
Derivative Asset [Abstract]    
Derivative asset, Netting (87) (51)
Total assets 1,439 1,435
Recurring | Current Derivative Liability    
Liabilities [Abstract]    
Derivative liability, netting 464 964
Derivative Liabilities, net (57) (77)
Recurring | Noncurrent Derivative Liability    
Liabilities [Abstract]    
Derivative liability, netting 98 61
Derivative Liabilities, net (86) (8)
Recurring | Restricted Assets    
Assets [Abstract]    
Cash equivalents 8 105
Recurring | Other Investments    
Assets [Abstract]    
Cash equivalents 8 7
Recurring | Natural Gas    
Derivative Asset [Abstract]    
Derivative asset, Netting (285) (681)
Derivative assets, net 102 106
Liabilities [Abstract]    
Derivative liability, netting 294 679
Derivative Liabilities, net (89) (39)
Recurring | Electricity    
Derivative Asset [Abstract]    
Derivative asset, Netting (232) (280)
Derivative assets, net 75 62
Liabilities [Abstract]    
Derivative liability, netting 253 298
Derivative Liabilities, net (52) (44)
Recurring | Other    
Derivative Asset [Abstract]    
Derivative asset, Netting (2) (42)
Derivative assets, net 3 3
Liabilities [Abstract]    
Derivative liability, netting 8 45
Derivative Liabilities, net (2) 0
Recurring | Other derivative contracts    
Derivative Asset [Abstract]    
Derivative asset, Netting (9) (3)
Derivative assets, net 3 1
Liabilities [Abstract]    
Derivative liability, netting 7 3
Derivative Liabilities, net 0 (2)
Recurring | Level 1    
Assets [Abstract]    
Cash equivalents 13 13
Nuclear decommissioning trusts 759 792
Other Investments 149 100
Derivative Asset [Abstract]    
Derivative asset, gross 195 597
Total assets 1,116 1,502
Liabilities [Abstract]    
Derivative Liabilities (220) (610)
Net Assets (Liabilities) at the end of the period 896 892
Recurring | Level 1 | Current Asset    
Derivative Asset [Abstract]    
Total assets 174 582
Recurring | Level 1 | Noncurrent Asset    
Derivative Asset [Abstract]    
Total assets 942 920
Recurring | Level 1 | Current Derivative Liability    
Liabilities [Abstract]    
Derivative Liabilities (174) (572)
Recurring | Level 1 | Noncurrent Derivative Liability    
Liabilities [Abstract]    
Derivative Liabilities (46) (38)
Recurring | Level 1 | Natural Gas    
Derivative Asset [Abstract]    
Derivative asset, gross 193 555
Liabilities [Abstract]    
Derivative Liabilities (218) (578)
Recurring | Level 1 | Electricity    
Derivative Asset [Abstract]    
Derivative asset, gross 0 0
Liabilities [Abstract]    
Derivative Liabilities 0 0
Recurring | Level 1 | Other    
Derivative Asset [Abstract]    
Derivative asset, gross 2 42
Liabilities [Abstract]    
Derivative Liabilities (2) (32)
Recurring | Level 1 | Other derivative contracts    
Derivative Asset [Abstract]    
Derivative asset, gross 0 0
Liabilities [Abstract]    
Derivative Liabilities 0 0
Recurring | Level 2    
Assets [Abstract]    
Cash equivalents 3 99
Nuclear decommissioning trusts 477 449
Other Investments 0 50
Derivative Asset [Abstract]    
Derivative asset, gross 342 439
Total assets 822 1,037
Liabilities [Abstract]    
Derivative Liabilities (307) (382)
Net Assets (Liabilities) at the end of the period 515 655
Recurring | Level 2 | Current Asset    
Derivative Asset [Abstract]    
Total assets 284 504
Recurring | Level 2 | Noncurrent Asset    
Derivative Asset [Abstract]    
Total assets 538 533
Recurring | Level 2 | Current Derivative Liability    
Liabilities [Abstract]    
Derivative Liabilities (260) (357)
Recurring | Level 2 | Noncurrent Derivative Liability    
Liabilities [Abstract]    
Derivative Liabilities (47) (25)
Recurring | Level 2 | Natural Gas    
Derivative Asset [Abstract]    
Derivative asset, gross 91 140
Liabilities [Abstract]    
Derivative Liabilities (57) (78)
Recurring | Level 2 | Electricity    
Derivative Asset [Abstract]    
Derivative asset, gross 239 295
Liabilities [Abstract]    
Derivative Liabilities (243) (290)
Recurring | Level 2 | Other    
Derivative Asset [Abstract]    
Derivative asset, gross 0 0
Liabilities [Abstract]    
Derivative Liabilities 0 (9)
Recurring | Level 2 | Other derivative contracts    
Derivative Asset [Abstract]    
Derivative asset, gross 12 4
Liabilities [Abstract]    
Derivative Liabilities (7) (5)
Recurring | Level 3    
Assets [Abstract]    
Cash equivalents 0 0
Nuclear decommissioning trusts 0 0
Other Investments 0 0
Derivative Asset [Abstract]    
Derivative asset, gross 174 142
Total assets 174 142
Liabilities [Abstract]    
Derivative Liabilities (178) (118)
Net Assets (Liabilities) at the end of the period (4) 24
Recurring | Level 3 | Current Asset    
Derivative Asset [Abstract]    
Total assets 128 109
Recurring | Level 3 | Noncurrent Asset    
Derivative Asset [Abstract]    
Total assets 46 33
Recurring | Level 3 | Current Derivative Liability    
Liabilities [Abstract]    
Derivative Liabilities (87) (112)
Recurring | Level 3 | Noncurrent Derivative Liability    
Liabilities [Abstract]    
Derivative Liabilities (91) (6)
Recurring | Level 3 | Natural Gas    
Derivative Asset [Abstract]    
Derivative asset, gross 103 92
Liabilities [Abstract]    
Derivative Liabilities (108) (62)
Recurring | Level 3 | Electricity    
Derivative Asset [Abstract]    
Derivative asset, gross 68 47
Liabilities [Abstract]    
Derivative Liabilities (62) (52)
Recurring | Level 3 | Other    
Derivative Asset [Abstract]    
Derivative asset, gross 3 3
Liabilities [Abstract]    
Derivative Liabilities (8) (4)
Recurring | Level 3 | Other derivative contracts    
Derivative Asset [Abstract]    
Derivative asset, gross 0 0
Liabilities [Abstract]    
Derivative Liabilities 0 0
DTE Electric    
Assets [Abstract]    
Nuclear decommissioning trusts 1,236 1,241
DTE Electric | Recurring    
Assets [Abstract]    
Cash equivalents 8 104
Nuclear decommissioning trusts 1,236 1,241
Other Investments 8 147
Derivative Asset [Abstract]    
Derivative assets, net 3 3
Total assets 1,255 1,495
DTE Electric | Recurring | Current Asset    
Derivative Asset [Abstract]    
Total assets 11 107
DTE Electric | Recurring | Noncurrent Asset    
Derivative Asset [Abstract]    
Total assets 1,244 1,388
DTE Electric | Recurring | Restricted Assets    
Assets [Abstract]    
Cash equivalents   96
DTE Electric | Recurring | Other Investments    
Assets [Abstract]    
Cash equivalents   8
DTE Electric | Recurring | Level 1    
Assets [Abstract]    
Cash equivalents 5 5
Nuclear decommissioning trusts 759 792
Other Investments 8 97
Derivative Asset [Abstract]    
Derivative asset, gross 0 0
Total assets 772 894
DTE Electric | Recurring | Level 1 | Current Asset    
Derivative Asset [Abstract]    
Total assets 5 5
DTE Electric | Recurring | Level 1 | Noncurrent Asset    
Derivative Asset [Abstract]    
Total assets 767 889
DTE Electric | Recurring | Level 2    
Assets [Abstract]    
Cash equivalents 3 99
Nuclear decommissioning trusts 477 449
Other Investments 0 50
Derivative Asset [Abstract]    
Derivative asset, gross 0 0
Total assets 480 598
DTE Electric | Recurring | Level 2 | Current Asset    
Derivative Asset [Abstract]    
Total assets 3 99
DTE Electric | Recurring | Level 2 | Noncurrent Asset    
Derivative Asset [Abstract]    
Total assets 477 499
DTE Electric | Recurring | Level 3    
Assets [Abstract]    
Cash equivalents 0 0
Nuclear decommissioning trusts 0 0
Other Investments 0 0
Derivative Asset [Abstract]    
Derivative asset, gross 3 3
Total assets 3 3
DTE Electric | Recurring | Level 3 | Current Asset    
Derivative Asset [Abstract]    
Total assets 3 3
DTE Electric | Recurring | Level 3 | Noncurrent Asset    
Derivative Asset [Abstract]    
Total assets 0 0
Equity | Recurring | Other Investments    
Assets [Abstract]    
Investments at fair value $ 149 $ 150