Short-Term Credit Arrangements and Borrowings (Tables)

9 Months Ended

Sep. 30, 2018

Short-term Debt [Abstract]

Schedule of Line of Credit Facilities

The availability under the facilities in place at September 30, 2018 is shown in the following table:

	DTE Energy		DTE Electric		DTE Gas		Total
	(In millions)
Unsecured letter of credit facility, expiring in February 2019	$	150	$	—	$	—	$	150
Unsecured letter of credit facility, expiring in September 2019	70		—		—		70
Unsecured revolving credit facility, expiring April 2022	1,200		400		300		1,900
	1,420		400		300		2,120
Amounts outstanding at September 30, 2018
Commercial paper issuances	—		51		26		77
Letters of credit	159		—		—		159
	159		51		26		236
Net availability at September 30, 2018	$	1,261	$	349	$	274	$	1,884