Long-Term Debt (Tables)

12 Months Ended

Dec. 31, 2011

Long-term Debt, Unclassified [Abstract]

Schedule of Long-term Debt Instruments [Table Text Block]

	2011			2010
	(In millions)
Mortgage bonds, notes, and other
DTE Energy Debt, Unsecured
5.5% due 2013 to 2033	$	1,298		$	1,597
Detroit Edison Taxable Debt, Principally Secured
5.3% due 2012 to 2041	3,515			2,915
Detroit Edison Tax-Exempt Revenue Bonds (2)
5.1% due 2012 to 2038	893			1,283
MichCon Taxable Debt, Principally Secured
6.1% due 2012 to 2033	889			889
Other Long-Term Debt, Including Non-Recourse Debt	165			195
	6,760			6,879
Less amount due within one year	(355		)	(765		)
	$	6,405		$	6,114
Securitization bonds
6.5% due 2012 to 2015	$	643		$	793
Less amount due within one year	(164		)	(150		)
	$	479		$	643
Junior Subordinated Debentures
6.5% due 2061	$	280		$	—
Trust preferred-linked securities
7.8% due 2032	$	—		$	186
7.5% due 2044	—			103
	$	—		$	289

Schedule of Issued Debt [Table Text Block]

Company	Month Issued	Type	Interest Rate		Maturity	Amount
	(In millions)
Detroit Edison	April	Tax-Exempt Revenue Bonds (1)	2.35	%	2024	$	31
Detroit Edison	May	Mortgage Bonds (2)	3.90	%	2021	250
DTE Energy	May	Senior Notes (3)	Variable (4)		2013	300
Detroit Edison	September	Mortgage Bonds (5)	4.31	%	2023	102
Detroit Edison	September	Mortgage Bonds (5)	4.46	%	2026	77
Detroit Edison	September	Mortgage Bonds (5)	5.67	%	2041	46
Detroit Edison	September	Tax-Exempt Revenue Bonds (6)	2.13	%	2030	82
Detroit Edison	September	Mortgage Bonds (7)	4.50	%	2041	140
DTE Energy	December	Junior Subordinated Debentures (8)	6.50	%	2061	280
						$	1,308

Schedule of Extinguishment of Debt [Table Text Block]

Company	Month Retired	Type	Interest Rate	Maturity	Amount
	(In millions)
Detroit Edison	May	Tax-Exempt Revenue Bonds	6.95%	2011	$	26
DTE Energy	June	Senior Notes	7.05%	2011	600
Detroit Edison	September	Tax-Exempt Revenue Bonds	5.55%	2029	118
Detroit Edison	September	Tax-Exempt Revenue Bonds	5.65%	2029	67
Detroit Edison	September	Tax-Exempt Revenue Bonds	5.65%	2029	40
Detroit Edison	September	Tax-Exempt Revenue Bonds	5.45%	2029	140
DTE Energy	December	Trust Preferred-Linked Securities	7.80%	2032	186
DTE Energy	December	Trust Preferred-Linked Securities	7.50%	2044	103
					$	1,280

Schedule of Maturities of Long-term Debt [Table Text Block]

	2012		2013		2014		2015		2016		2017 and Thereafter		Total
	(In millions)
Amount to mature	$	519	$	811	$	892	$	476	$	465	$	4,530	$	7,693