Long-Term Debt (Details)	9 Months Ended
	Sep. 30, 2018 USD ($)
Debt Instrument [Line Items]
Debt issued	$ 1,445,000,000
Debt redeemed	$ 105,000,000
DTE Energy | Senior Notes | August 2018 3.70% Senior Notes Maturing 2023
Debt Instrument [Line Items]
Interest rate	3.70%
Debt issued	$ 600,000,000
DTE Energy | Other Long-Term Debt
Debt Instrument [Line Items]
Debt redeemed	$ 5,000,000
DTE Electric | Mortgage Bonds | May 2018 4.05% Mortgage Bonds Maturing 2048
Debt Instrument [Line Items]
Interest rate	4.05%
Debt issued	$ 525,000,000
DTE Gas | Mortgage Bonds | August 2018 3.81% Mortgage Bonds Maturing in 2028
Debt Instrument [Line Items]
Interest rate	3.81%
Debt issued	$ 195,000,000
DTE Gas | Mortgage Bonds | August 2018 4.14% Mortgage Bonds Maturing in 2048
Debt Instrument [Line Items]
Interest rate	4.14%
Debt issued	$ 125,000,000
DTE Gas | Senior Notes | April 2018 6.04% Senior Notes Maturing 2018
Debt Instrument [Line Items]
Interest rate	6.04%
Debt redeemed	$ 100,000,000