Long-Term Debt (Details) - USD ($)	6 Months Ended
	Jun. 30, 2018	Aug. 31, 2018
Debt Instrument [Line Items]
Debt issued	$ 525,000,000
Debt redeemed	102,000,000
Other Long-Term Debt | DTE Energy
Debt Instrument [Line Items]
Debt redeemed	$ 2,000,000
DTE Electric | Mortgage Bonds | May 2018 4.05% Mortgage Bonds Maturing in 2048
Debt Instrument [Line Items]
Interest rate	4.05%
Debt issued	$ 525,000,000
DTE Gas | Mortgage Bonds | August 2018 3.81% First Mortgage Bonds Maturing 2028 | Forecast
Debt Instrument [Line Items]
Interest rate		3.81%
Debt issued		$ 195,000,000
DTE Gas | Mortgage Bonds | August 2018 3.81% First Mortgage Bonds Maturing 2048 | Forecast
Debt Instrument [Line Items]
Interest rate		4.14%
Debt issued		$ 125,000,000
DTE Gas | Senior Notes | 6.04% Senior Notes Due 2018
Debt Instrument [Line Items]
Interest rate	6.04%
Debt redeemed	$ 100,000,000