Contractual interest rate for funds borrowed, under the debt agreement.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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-Topic 470
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-Subparagraph (SX 210.5-02.22(a)(1))
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
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The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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-Publisher FASB
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Long-Term Debt (Schedule of Debt Redeemed) (Details) - USD ($) $ in Millions	1 Months Ended				3 Months Ended	6 Months Ended
	Jul. 27, 2021	Jun. 30, 2021	May 31, 2021	Apr. 30, 2021	Jun. 30, 2021	Jun. 30, 2021	Jun. 30, 2020
Debt Instrument, Redemption [Line Items]
Amount						$ 583	$ 300
Loss on extinguishment of debt					$ (8)	$ 8
Subsequent Event
Debt Instrument, Redemption [Line Items]
Amount	$ 2,247
Senior Notes \| 5.375% Junior Subordinated Debentures maturing in 2076
Debt Instrument, Redemption [Line Items]
Interest rate		5.375%			5.375%	5.375%
Amount		$ 300
Senior Notes \| 3.30% Senior Notes maturing in 2022 \| Subsequent Event
Debt Instrument, Redemption [Line Items]
Interest rate	3.30%
Amount	$ 300
Senior Notes \| 2.60% Senior Notes maturing in 2022 \| Subsequent Event
Debt Instrument, Redemption [Line Items]
Interest rate	2.60%
Amount	$ 300
Senior Notes \| 3.70% Senior Notes maturing in 2023 \| Subsequent Event
Debt Instrument, Redemption [Line Items]
Interest rate	3.70%
Amount	$ 600
Senior Notes \| 3.85% Senior Notes maturing in 2023 \| Subsequent Event
Debt Instrument, Redemption [Line Items]
Interest rate	3.85%
Amount	$ 135
Senior Notes \| 3.50% Senior Notes maturing in 2024 \| Subsequent Event
Debt Instrument, Redemption [Line Items]
Interest rate	3.50%
Amount	$ 350
Senior Notes \| 3.80% Senior Notes maturing in 2027 \| Subsequent Event
Debt Instrument, Redemption [Line Items]
Interest rate	3.80%
Amount	$ 350
Senior Notes \| 3.40% Senior Notes maturing in 2029 \| Subsequent Event
Debt Instrument, Redemption [Line Items]
Interest rate	3.40%
Amount	$ 21
Senior Notes \| 6.375% Senior Notes maturing in 2033 \| Subsequent Event
Debt Instrument, Redemption [Line Items]
Interest rate	6.375%
Amount	$ 191
DTE Electric
Debt Instrument, Redemption [Line Items]
Amount						$ 283	$ 300
DTE Electric \| Mortgage Bonds \| 3.90% Mortgage bonds maturing in 2021
Debt Instrument, Redemption [Line Items]
Interest rate				3.90%
Amount				$ 250
DTE Electric \| Mortgage Bonds \| 7.00% Mortgage Bonds maturing in 2021
Debt Instrument, Redemption [Line Items]
Interest rate			7.00%
Amount			$ 33