Accumulated Other Comprehensive Income (Details 1) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Reclassification Out of Accumulated Other Comprehensive Income [Line Items]
Other operating expenses	$ 916	$ 1,021	$ 1,973	$ 2,203
Interest expense	282	262	561	527
Investment income (loss)	3	(29)	(14)	(51)
Total before taxes	(302)	(90)	(668)	(260)
Income taxes (benefits)	115	26	259	74
Net of tax	(187)	(64)	(409)	(272)
FES
Reclassification Out of Accumulated Other Comprehensive Income [Line Items]
Other operating expenses	353	468	766	920
Investment income (loss)	(1)	(24)	(14)	(44)
Total before taxes	25	154	30	313
Income taxes (benefits)	(4)	(67)	(6)	(123)
Reclassifications from AOCI | Gains & losses on cash flow hedges
Reclassification Out of Accumulated Other Comprehensive Income [Line Items]
Total before taxes	1	(1)	2	(1)
Income taxes (benefits)	(1)	1	(1)	1
Net of tax	0	0	1	0
Reclassifications from AOCI | Gains & losses on cash flow hedges | FES
Reclassification Out of Accumulated Other Comprehensive Income [Line Items]
Income taxes (benefits)	0	1	0	2
Net of tax	(1)	(2)	(2)	(3)
Reclassifications from AOCI | Gains & losses on cash flow hedges | Commodity contracts
Reclassification Out of Accumulated Other Comprehensive Income [Line Items]
Other operating expenses	(1)	(3)	(2)	(5)
Reclassifications from AOCI | Gains & losses on cash flow hedges | Commodity contracts | FES
Reclassification Out of Accumulated Other Comprehensive Income [Line Items]
Other operating expenses	(1)	(3)	(2)	(5)
Reclassifications from AOCI | Gains & losses on cash flow hedges | Long-term debt
Reclassification Out of Accumulated Other Comprehensive Income [Line Items]
Interest expense	2	2	4	4
Reclassifications from AOCI | Unrealized gains on AFS securities
Reclassification Out of Accumulated Other Comprehensive Income [Line Items]
Investment income (loss)	(7)	(19)	(17)	(33)
Income taxes (benefits)	2	7	6	12
Net of tax	(5)	(12)	(11)	(21)
Reclassifications from AOCI | Unrealized gains on AFS securities | FES
Reclassification Out of Accumulated Other Comprehensive Income [Line Items]
Investment income (loss)	(5)	(18)	(15)	(32)
Income taxes (benefits)	2	6	6	11
Net of tax	(3)	(12)	(9)	(21)
Reclassifications from AOCI | Defined benefit pension and OPEB plans
Reclassification Out of Accumulated Other Comprehensive Income [Line Items]
Prior-service costs	(32)	(42)	(63)	(84)
Income taxes (benefits)	13	16	24	32
Net of tax	(19)	(26)	(39)	(52)
Reclassifications from AOCI | Defined benefit pension and OPEB plans | FES
Reclassification Out of Accumulated Other Comprehensive Income [Line Items]
Prior-service costs	(4)	(5)	(8)	(10)
Income taxes (benefits)	2	2	3	4
Net of tax	$ (2)	$ (3)	$ (5)	$ (6)