Significant Accounting Policies (Income Taxes) (Details)	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Schedule of Income Taxes [Line Items]
Effective Tax Rate	11.00%	2.00%	8.00%	8.00%
DTE Electric
Schedule of Income Taxes [Line Items]
Effective Tax Rate	10.00%	12.00%	10.00%	12.00%

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32687-109319

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration