Accumulated Other Comprehensive Income (Details 1) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013		Mar. 31, 2012
Reclassification Out of Accumulated Other Comprehensive Income [Line Items]
Other operating expenses	$ 884		$ 818
Investment income	(18)		(11)
Total before taxes	(312)		(528)
Income tax expense	116		222
Net of tax	(196)		(306)
Interest expense	256		246
Loss on debt redemptions	119		0
FES
Reclassification Out of Accumulated Other Comprehensive Income [Line Items]
Other operating expenses	380		295
Investment income	(17)		(6)
Total before taxes	(4)		(198)
Income tax expense	2		76
Net of tax	(2)		(122)
Loss on debt redemptions	73		0
Reclassifications from AOCI | Gains & Losses on Cash Flow Hedges
Reclassification Out of Accumulated Other Comprehensive Income [Line Items]
Total before taxes	1	[1]	(3)	[1]
Income tax expense	0	[1]	0	[1]
Net of tax	1	[1]	(3)	[1]
Reclassifications from AOCI | Gains & Losses on Cash Flow Hedges | FES
Reclassification Out of Accumulated Other Comprehensive Income [Line Items]
Total before taxes	(1)	[1]	(5)	[1]
Income tax expense	0	[1]	(1)	[1]
Net of tax	(1)	[1]	(4)	[1]
Reclassifications from AOCI | Gains & Losses on Cash Flow Hedges | Power contracts
Reclassification Out of Accumulated Other Comprehensive Income [Line Items]
Other operating expenses	(3)	[1]	(5)	[1]
Reclassifications from AOCI | Gains & Losses on Cash Flow Hedges | Power contracts | FES
Reclassification Out of Accumulated Other Comprehensive Income [Line Items]
Other operating expenses	(3)	[1]	(5)	[1]
Reclassifications from AOCI | Gains & Losses on Cash Flow Hedges | Long-term debt
Reclassification Out of Accumulated Other Comprehensive Income [Line Items]
Interest expense ($2) and Loss on debt redemptions ($2) in 2013 and interest expense ($2) in 2012	4	[1]	2	[1]
Interest expense	2	[1]	2	[1]
Loss on debt redemptions	(2)	[1]
Reclassifications from AOCI | Gains & Losses on Cash Flow Hedges | Long-term debt | FES
Reclassification Out of Accumulated Other Comprehensive Income [Line Items]
Loss on debt redemptions	2	[1]	0	[1]
Reclassifications from AOCI | Unrealized Gains on AFS Securities
Reclassification Out of Accumulated Other Comprehensive Income [Line Items]
Investment income	(19)	[1]	(5)	[1]
Income tax expense	(7)	[1]	(2)	[1]
Net of tax	(12)	[1]	(3)	[1]
Reclassifications from AOCI | Unrealized Gains on AFS Securities | FES
Reclassification Out of Accumulated Other Comprehensive Income [Line Items]
Investment income	(16)	[1]	(4)	[1]
Income tax expense	(6)	[1]	(1)	[1]
Net of tax	(10)	[1]	(3)	[1]
Reclassifications from AOCI | Defined Benefit Pension & OPEB Plans
Reclassification Out of Accumulated Other Comprehensive Income [Line Items]
Prior-service costs	(47)	[1],[2]	(48)	[1],[2]
Income tax expense	(19)	[1]	(19)	[1]
Net of tax	(28)	[1]	(29)	[1]
Reclassifications from AOCI | Defined Benefit Pension & OPEB Plans | FES
Reclassification Out of Accumulated Other Comprehensive Income [Line Items]
Prior-service costs	(5)	[1],[2]	(5)	[1],[2]
Income tax expense	(1)	[1]	(1)	[1]
Net of tax	$ (4)	[1]	$ (4)	[1]

[1] Parenthesis represent credits from AOCI

[2] These accumulated other comprehensive income components are included in the computation of net periodic pension cost. See Note 3, Pensions and Other Postemployment Benefits for additional details.