Fair Value (Assets and Liabilities Recorded at Fair Value on a Recurring Basis) (Details) - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Derivative assets
Derivative assets, gross	$ 397	$ 652
Derivative asset, netting	(255)	(498)
Derivative assets, net	142	154
Derivative liabilities
Derivative liabilities, gross	(397)	(657)
Derivative liability, netting	270	511
Derivative liabilities, net	(127)	(146)
Current derivative liabilities
Derivative liabilities
Derivative liabilities, gross	(289)	(558)
Noncurrent derivative liabilities
Derivative liabilities
Derivative liabilities, gross	(108)	(99)
Natural gas
Derivative assets
Derivative assets, gross	207	357
Derivative asset, netting	(118)	(256)
Derivative assets, net	89	101
Derivative liabilities
Derivative liabilities, gross	(196)	(378)
Derivative liability, netting	126	263
Derivative liabilities, net	(70)	(115)
Electricity
Derivative assets
Derivative assets, gross	183	285
Derivative asset, netting	(135)	(241)
Derivative assets, net	48	44
Derivative liabilities
Derivative liabilities, gross	(198)	(275)
Derivative liability, netting	142	246
Derivative liabilities, net	(56)	(29)
Other
Derivative assets
Derivative assets, gross	5	9
Derivative asset, netting	0	0
Derivative assets, net	5	9
Derivative liabilities
Derivative liabilities, gross	(1)	(1)
Derivative liability, netting	0	1
Derivative liabilities, net	(1)	0
Foreign currency exchange contracts
Derivative assets
Derivative assets, gross	2	1
Derivative asset, netting	(2)	(1)
Derivative assets, net	0	0
Derivative liabilities
Derivative liabilities, gross	(2)	(3)
Derivative liability, netting	2	1
Derivative liabilities, net	0	(2)
Recurring
Assets
Cash equivalents	16	19
Derivative assets
Derivative asset, netting	(255)	(498)
Derivative assets, net	142	154
Total assets	1,830	1,859
Private equity securities	5	5
Derivative liabilities
Derivative liability, netting	270	511
Derivative liabilities, net	(127)	(146)
Net Assets (Liabilities) at the end of the period	1,703	1,713
Net Assets (Liabilities) at the end of the period, netting	15	13
Recurring | DTE Electric
Assets
Cash equivalents	8	11
Derivative assets
Total assets	1,505	1,523
Private equity securities	5	5
Recurring | Current assets
Derivative assets
Derivative asset, netting	(210)	(437)
Total assets	100	122
Recurring | Current assets | DTE Electric
Derivative assets
Total assets	13	20
Recurring | Noncurrent assets
Derivative assets
Derivative asset, netting	(45)	(61)
Total assets	1,730	1,737
Private equity securities	5	5
Recurring | Noncurrent assets | DTE Electric
Derivative assets
Total assets	1,492	1,503
Private equity securities	5	5
Recurring | Current derivative liabilities
Derivative liabilities
Derivative liability, netting	220	459
Derivative liabilities, net	(69)	(99)
Recurring | Noncurrent derivative liabilities
Derivative liabilities
Derivative liability, netting	50	52
Derivative liabilities, net	(58)	(47)
Recurring | Restricted assets
Assets
Cash equivalents	8	8
Recurring | Other
Assets
Cash equivalents	8	11
Recurring | Other | DTE Electric
Assets
Cash equivalents	8	11
Recurring | Natural gas
Derivative assets
Derivative asset, netting	(118)	(256)
Derivative assets, net	89	101
Derivative liabilities
Derivative liability, netting	126	263
Derivative liabilities, net	(70)	(115)
Recurring | Electricity
Derivative assets
Derivative asset, netting	(135)	(241)
Derivative assets, net	48	44
Derivative liabilities
Derivative liability, netting	142	246
Derivative liabilities, net	(56)	(29)
Recurring | Other
Derivative assets
Derivative asset, netting	0	0
Derivative assets, net	5	9
Derivative liabilities
Derivative liability, netting	0	1
Derivative liabilities, net	(1)	0
Recurring | Foreign currency exchange contracts
Derivative assets
Derivative asset, netting	(2)	(1)
Derivative assets, net	0	0
Derivative liabilities
Derivative liability, netting	2	1
Derivative liabilities, net	0	(2)
Recurring | Derivative assets — FTRs | DTE Electric
Derivative assets
Derivative assets, net	5	9
Recurring | Cash equivalents
Assets
Nuclear decommissioning trusts	13	14
Other investments	4	4
Recurring | Cash equivalents | DTE Electric
Assets
Nuclear decommissioning trusts	13	14
Recurring | Equity securities
Assets
Nuclear decommissioning trusts	933	978
Other investments	117	118
Recurring | Equity securities | DTE Electric
Assets
Nuclear decommissioning trusts	933	978
Other investments	11	11
Recurring | Fixed income securities
Assets
Nuclear decommissioning trusts	530	495
Other investments	70	72
Recurring | Fixed income securities | DTE Electric
Assets
Nuclear decommissioning trusts	530	495
Recurring | Level 1
Assets
Cash equivalents	16	16
Derivative assets
Derivative assets, gross	49	148
Total assets	1,216	1,368
Derivative liabilities
Derivative liabilities, gross	(58)	(141)
Net Assets (Liabilities) at the end of the period	1,158	1,227
Recurring | Level 1 | DTE Electric
Assets
Cash equivalents	8	8
Derivative assets
Total assets	979	1,029
Recurring | Level 1 | Current assets
Derivative assets
Total assets	65	157
Recurring | Level 1 | Current assets | DTE Electric
Derivative assets
Total assets	8	8
Recurring | Level 1 | Noncurrent assets
Derivative assets
Total assets	1,151	1,211
Recurring | Level 1 | Noncurrent assets | DTE Electric
Derivative assets
Total assets	971	1,021
Recurring | Level 1 | Current derivative liabilities
Derivative liabilities
Derivative liabilities, gross	(53)	(137)
Recurring | Level 1 | Noncurrent derivative liabilities
Derivative liabilities
Derivative liabilities, gross	(5)	(4)
Recurring | Level 1 | Natural gas
Derivative assets
Derivative assets, gross	49	148
Derivative liabilities
Derivative liabilities, gross	(58)	(141)
Recurring | Level 1 | Electricity
Derivative assets
Derivative assets, gross	0	0
Derivative liabilities
Derivative liabilities, gross	0	0
Recurring | Level 1 | Other
Derivative assets
Derivative assets, gross	0	0
Derivative liabilities
Derivative liabilities, gross	0	0
Recurring | Level 1 | Foreign currency exchange contracts
Derivative assets
Derivative assets, gross	0	0
Derivative liabilities
Derivative liabilities, gross	0	0
Recurring | Level 1 | Derivative assets — FTRs | DTE Electric
Derivative assets
Derivative assets, net	0	0
Recurring | Level 1 | Cash equivalents
Assets
Nuclear decommissioning trusts	13	14
Other investments	4	4
Recurring | Level 1 | Cash equivalents | DTE Electric
Assets
Nuclear decommissioning trusts	13	14
Recurring | Level 1 | Equity securities
Assets
Nuclear decommissioning trusts	933	978
Other investments	117	118
Recurring | Level 1 | Equity securities | DTE Electric
Assets
Nuclear decommissioning trusts	933	978
Other investments	11	11
Recurring | Level 1 | Fixed income securities
Assets
Nuclear decommissioning trusts	14	18
Other investments	70	72
Recurring | Level 1 | Fixed income securities | DTE Electric
Assets
Nuclear decommissioning trusts	14	18
Recurring | Level 2
Assets
Cash equivalents	0	3
Derivative assets
Derivative assets, gross	256	356
Total assets	772	836
Derivative liabilities
Derivative liabilities, gross	(228)	(359)
Net Assets (Liabilities) at the end of the period	544	477
Recurring | Level 2 | DTE Electric
Assets
Cash equivalents	0	3
Derivative assets
Total assets	516	480
Recurring | Level 2 | Current assets
Derivative assets
Total assets	194	298
Recurring | Level 2 | Current assets | DTE Electric
Derivative assets
Total assets	0	3
Recurring | Level 2 | Noncurrent assets
Derivative assets
Total assets	578	538
Recurring | Level 2 | Noncurrent assets | DTE Electric
Derivative assets
Total assets	516	477
Recurring | Level 2 | Current derivative liabilities
Derivative liabilities
Derivative liabilities, gross	(183)	(313)
Recurring | Level 2 | Noncurrent derivative liabilities
Derivative liabilities
Derivative liabilities, gross	(45)	(46)
Recurring | Level 2 | Natural gas
Derivative assets
Derivative assets, gross	92	112
Derivative liabilities
Derivative liabilities, gross	(62)	(111)
Recurring | Level 2 | Electricity
Derivative assets
Derivative assets, gross	162	243
Derivative liabilities
Derivative liabilities, gross	(164)	(245)
Recurring | Level 2 | Other
Derivative assets
Derivative assets, gross	0	0
Derivative liabilities
Derivative liabilities, gross	0	0
Recurring | Level 2 | Foreign currency exchange contracts
Derivative assets
Derivative assets, gross	2	1
Derivative liabilities
Derivative liabilities, gross	(2)	(3)
Recurring | Level 2 | Derivative assets — FTRs | DTE Electric
Derivative assets
Derivative assets, net	0	0
Recurring | Level 2 | Cash equivalents
Assets
Nuclear decommissioning trusts	0	0
Other investments	0	0
Recurring | Level 2 | Cash equivalents | DTE Electric
Assets
Nuclear decommissioning trusts	0	0
Recurring | Level 2 | Equity securities
Assets
Nuclear decommissioning trusts	0	0
Other investments	0	0
Recurring | Level 2 | Equity securities | DTE Electric
Assets
Nuclear decommissioning trusts	0	0
Other investments	0	0
Recurring | Level 2 | Fixed income securities
Assets
Nuclear decommissioning trusts	516	477
Other investments	0	0
Recurring | Level 2 | Fixed income securities | DTE Electric
Assets
Nuclear decommissioning trusts	516	477
Recurring | Level 3
Assets
Cash equivalents	0	0
Derivative assets
Derivative assets, gross	92	148
Total assets	92	148
Derivative liabilities
Derivative liabilities, gross	(111)	(157)
Net Assets (Liabilities) at the end of the period	(19)	(9)
Recurring | Level 3 | DTE Electric
Assets
Cash equivalents	0	0
Derivative assets
Total assets	5	9
Recurring | Level 3 | Current assets
Derivative assets
Total assets	51	104
Recurring | Level 3 | Current assets | DTE Electric
Derivative assets
Total assets	5	9
Recurring | Level 3 | Noncurrent assets
Derivative assets
Total assets	41	44
Recurring | Level 3 | Noncurrent assets | DTE Electric
Derivative assets
Total assets	0	0
Recurring | Level 3 | Current derivative liabilities
Derivative liabilities
Derivative liabilities, gross	(53)	(108)
Recurring | Level 3 | Noncurrent derivative liabilities
Derivative liabilities
Derivative liabilities, gross	(58)	(49)
Recurring | Level 3 | Natural gas
Derivative assets
Derivative assets, gross	66	97
Derivative liabilities
Derivative liabilities, gross	(76)	(126)
Recurring | Level 3 | Electricity
Derivative assets
Derivative assets, gross	21	42
Derivative liabilities
Derivative liabilities, gross	(34)	(30)
Recurring | Level 3 | Other
Derivative assets
Derivative assets, gross	5	9
Derivative liabilities
Derivative liabilities, gross	(1)	(1)
Recurring | Level 3 | Foreign currency exchange contracts
Derivative assets
Derivative assets, gross	0	0
Derivative liabilities
Derivative liabilities, gross	0	0
Recurring | Level 3 | Derivative assets — FTRs | DTE Electric
Derivative assets
Derivative assets, net	5	9
Recurring | Level 3 | Cash equivalents
Assets
Nuclear decommissioning trusts	0	0
Other investments	0	0
Recurring | Level 3 | Cash equivalents | DTE Electric
Assets
Nuclear decommissioning trusts	0	0
Recurring | Level 3 | Equity securities
Assets
Nuclear decommissioning trusts	0	0
Other investments	0	0
Recurring | Level 3 | Equity securities | DTE Electric
Assets
Nuclear decommissioning trusts	0	0
Other investments	0	0
Recurring | Level 3 | Fixed income securities
Assets
Nuclear decommissioning trusts	0	0
Other investments	0	0
Recurring | Level 3 | Fixed income securities | DTE Electric
Assets
Nuclear decommissioning trusts	0	0
Private Equity Funds | Recurring
Assets
Nuclear decommissioning trusts	5	5
Derivative assets
Private equity securities	5	5
Private Equity Funds | Recurring | DTE Electric
Assets
Nuclear decommissioning trusts	5	5
Derivative assets
Private equity securities	5	5
Private Equity Funds | Recurring | Level 1
Assets
Nuclear decommissioning trusts	0	0
Private Equity Funds | Recurring | Level 1 | DTE Electric
Assets
Nuclear decommissioning trusts	0	0
Private Equity Funds | Recurring | Level 2
Assets
Nuclear decommissioning trusts	0	0
Private Equity Funds | Recurring | Level 2 | DTE Electric
Assets
Nuclear decommissioning trusts	0	0
Private Equity Funds | Recurring | Level 3
Assets
Nuclear decommissioning trusts	0	0
Private Equity Funds | Recurring | Level 3 | DTE Electric
Assets
Nuclear decommissioning trusts	$ 0	$ 0