Fair Value (Reconciliation of Level 3 Assets and Liabilities at Fair Value on a Recurring Basis) (Details) - Recurring - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Net Assets (Liabilities) as of beginning of period	$ (23)	$ (57)	$ (88)	$ (4)
Transfers into Level 3 from Level 2	0	0	0	0
Transfers from Level 3 into Level 2	0	0	0	(1)
Total gains (losses):
Included in earnings	15	(22)	58	(101)
Recorded in/Change in fair value recorded in Regulatory liabilities	11	6	13	4
Purchases, issuances, and settlements
Purchases	0	1
Issuances			0	1
Settlements	(9)	3	11	32
Net Assets (Liabilities) as of end of period	(6)	(69)	(6)	(69)
The amount of total gains (losses) included in Net Income attributed to the change in unrealized gains (losses) related to assets and liabilities held at June 30, 2017 and 2016 and reflected in Operating Revenues — Non-utility operations and Fuel, purchased power, and gas — non-utility in DTE Energy's Consolidated Statements of Operations	0	(43)	32	(119)
DTE Electric
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Net Assets (Liabilities) as of beginning of period	1	1	2	3
Total gains (losses):
Recorded in/Change in fair value recorded in Regulatory liabilities	11	6	13	4
Purchases, issuances, and settlements
Settlements	(4)	(3)	(7)	(3)
Net Assets (Liabilities) as of end of period	8	4	8	4
The amount of total gains (losses) included in Regulatory liabilities attributed to the change in unrealized gains (losses) related to assets held at June 30, 2017 and 2016 and reflected in DTE Electric's Consolidated Statements of Financial Position	8	4	8	4
Natural Gas
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Net Assets (Liabilities) as of beginning of period	(15)	(34)	(96)	(5)
Transfers into Level 3 from Level 2	0	0	0	0
Transfers from Level 3 into Level 2	0	0	0	(1)
Total gains (losses):
Included in earnings	(6)	(36)	46	(56)
Recorded in/Change in fair value recorded in Regulatory liabilities	0	0	0	0
Purchases, issuances, and settlements
Purchases	0	0
Issuances			0	0
Settlements	4	8	33	0
Net Assets (Liabilities) as of end of period	(17)	(62)	(17)	(62)
The amount of total gains (losses) included in Net Income attributed to the change in unrealized gains (losses) related to assets and liabilities held at June 30, 2017 and 2016 and reflected in Operating Revenues — Non-utility operations and Fuel, purchased power, and gas — non-utility in DTE Energy's Consolidated Statements of Operations	(20)	(41)	16	(113)
Electricity
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Net Assets (Liabilities) as of beginning of period	(6)	(16)	9	6
Transfers into Level 3 from Level 2	0	0	0	0
Transfers from Level 3 into Level 2	0	0	0	0
Total gains (losses):
Included in earnings	21	12	11	(46)
Recorded in/Change in fair value recorded in Regulatory liabilities	0	0	0	0
Purchases, issuances, and settlements
Purchases	0	1
Issuances			0	1
Settlements	(9)	(3)	(14)	33
Net Assets (Liabilities) as of end of period	6	(6)	6	(6)
The amount of total gains (losses) included in Net Income attributed to the change in unrealized gains (losses) related to assets and liabilities held at June 30, 2017 and 2016 and reflected in Operating Revenues — Non-utility operations and Fuel, purchased power, and gas — non-utility in DTE Energy's Consolidated Statements of Operations	20	(4)	17	(7)
Other
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Net Assets (Liabilities) as of beginning of period	(2)	(7)	(1)	(5)
Transfers into Level 3 from Level 2	0	0	0	0
Transfers from Level 3 into Level 2	0	0	0	0
Total gains (losses):
Included in earnings	0	2	1	1
Recorded in/Change in fair value recorded in Regulatory liabilities	11	6	13	4
Purchases, issuances, and settlements
Purchases	0	0
Issuances			0	0
Settlements	(4)	(2)	(8)	(1)
Net Assets (Liabilities) as of end of period	5	(1)	5	(1)
The amount of total gains (losses) included in Net Income attributed to the change in unrealized gains (losses) related to assets and liabilities held at June 30, 2017 and 2016 and reflected in Operating Revenues — Non-utility operations and Fuel, purchased power, and gas — non-utility in DTE Energy's Consolidated Statements of Operations	$ 0	$ 2	$ (1)	$ 1