Short-Term Credit Arrangements and Borrowings (Tables)

9 Months Ended

Sep. 30, 2011

Short-Term Credit Arrangements and Borrowings [Abstract]

Schedule of Short-term Debt [Table Text Block]

The availability under these combined facilities at September 30, 2011 is shown in the following table:

(in Millions)	DTE Energy		Detroit Edison		MichCon		Total
Unsecured revolving credit facility, expiring August 2012	$	538	$	212	$	250	$	1,000
Unsecured revolving credit facility, expiring August 2013	562		63		175		800
Unsecured letter of credit facility, expiring in May 2013	50		—		—		50
Unsecured letter of credit facility, expiring in August 2015	125		—		—		125
Total credit facilities at September 30, 2011	$	1,275	$	275	$	425	$	1,975
Amounts outstanding at September 30, 2011:
Commercial paper issuances	126		49		100		275
Letters of credit outstanding at September 30, 2011	144		—		—		144
	270		49		100		419
Net availability at September 30, 2011	$	1,005	$	226	$	325	$	1,556