Leases (Future Minimum Lease Payments - Topic 842) (Details) $ in Millions	Jun. 30, 2019 USD ($)
Operating Leases
2019	$ 21
2020	32
2021	23
2022	16
2023	13
2024 and thereafter	61
Total future minimum lease payments	166
Imputed interest	(30)
Total	136
Finance Leases
2019	2
2020	4
2021	3
2022	0
2023	0
2024 and thereafter	0
Total future minimum lease payments	9
Imputed interest	0
Total	9
DTE Electric
Operating Leases
2019	9
2020	12
2021	11
2022	7
2023	6
2024 and thereafter	30
Total future minimum lease payments	75
Imputed interest	(14)
Total	61
Finance Leases
2019	2
2020	4
2021	3
2022	0
2023	0
2024 and thereafter	0
Total future minimum lease payments	9
Imputed interest	0
Total	$ 9