Long-Term Debt (Debt Issuances) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Oct. 31, 2020	Sep. 30, 2020	Aug. 31, 2020	Jul. 31, 2020	Apr. 30, 2020	Mar. 31, 2020	Feb. 29, 2020
Debt Instrument [Line Items]
Amount	$ 3,730,000,000
Unsecured Term Loan, Expiring in March 2021 | Unsecured
Debt Instrument [Line Items]
Repayment of debt	500,000,000
June 2020 Unsecured Term Loan, Expiring June 2021 | Unsecured
Debt Instrument [Line Items]
Repayment of debt	$ 167,000,000
Senior Notes | August 2020 1.05% Senior Notes Maturing In 2025
Debt Instrument [Line Items]
Interest Rate				1.05%
Amount				$ 800,000,000
Senior Notes | October 2020 0.55% Senior Notes Maturing In 2022
Debt Instrument [Line Items]
Interest Rate		0.55%
Amount		$ 750,000,000
Junior Subordinated Debentures | October 2020 4.375% Junior Subordinated Debentures Maturing In 2080
Debt Instrument [Line Items]
Interest Rate		4.38%
Amount		$ 230,000,000
Junior Subordinated Debentures | Series C, 2012, 5.25% Junior Subordinated Debentures Maturing 2062
Debt Instrument [Line Items]
Interest Rate	5.25%	5.25%
Repayment of debt	$ 200,000,000
DTE Electric | Mortgage Bonds | February 2020 2.25% Mortgage Bonds Maturing in 2030
Debt Instrument [Line Items]
Interest Rate								2.25%
Amount								$ 600,000,000
DTE Electric | Mortgage Bonds | February 2020 2.95% Mortgage Bonds Maturing In 2050
Debt Instrument [Line Items]
Interest Rate								2.95%
Amount								$ 500,000,000
DTE Electric | Mortgage Bonds | April 2020 2.63% Mortgage Bonds Maturing in 2031
Debt Instrument [Line Items]
Interest Rate						2.63%
Amount						$ 600,000,000
DTE Electric | Senior Notes | 4.89% Senior Notes Maturing 2020
Debt Instrument [Line Items]
Interest Rate	4.89%						4.89%
Repayment of debt	$ 300,000,000
DTE Electric | Senior Notes | 2010 Series B 3.45% Senior Notes Maturing 2020
Debt Instrument [Line Items]
Interest Rate	3.45%				3.45%
Repayment of debt	$ 300,000,000
DTE Electric | Senior Notes | 2008 Series KT Variable Rate Senior Notes Due 2020
Debt Instrument [Line Items]
Repayment of debt	$ 32,000,000
DTE Gas | Mortgage Bonds | August 2020 2.35% Mortgage Bonds Maturing In 2030
Debt Instrument [Line Items]
Interest Rate				2.35%
Amount				$ 125,000,000
DTE Gas | Mortgage Bonds | August 2020 3.20% Mortgage Bonds Maturing In 2050
Debt Instrument [Line Items]
Interest Rate				3.20%
Amount				$ 125,000,000
DTE Gas | Senior Notes | 2008 Series I 6.36% Senior Notes Maturing 2020
Debt Instrument [Line Items]
Interest Rate	6.36%		6.36%
Repayment of debt	$ 50,000,000