Consolidated Valuation and Qualifying Accounts (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Accumulated provision for uncollectible accounts - customers
Consolidated Valuation and Qualifying Accounts
Beginning Balance	$ 40,354	$ 37,303	$ 36,272
Charged to Income	68,733	84,026	78,521
Charged to Other Accounts	39,775	36,686	38,042
Deductions	97,232	117,661	115,532
Ending Balance	51,630	40,354	37,303
Accumulated provision for uncollectible accounts - customers | FES
Consolidated Valuation and Qualifying Accounts
Beginning Balance	16,188	16,441	16,591
Charged to Income	14,294	10,410	11,250
Charged to Other Accounts	0	0	0
Deductions	19,409	10,663	11,400
Ending Balance	11,073	16,188	16,441
Accumulated provision for uncollectible accounts - other
Consolidated Valuation and Qualifying Accounts
Beginning Balance	4,013	3,447	8,252
Charged to Income	(1,464)	4,328	663
Charged to Other Accounts	5,208	203	927
Deductions	4,781	3,965	6,395
Ending Balance	2,976	4,013	3,447
Accumulated provision for uncollectible accounts - other | FES
Consolidated Valuation and Qualifying Accounts
Beginning Balance	2,500	2,500	6,765
Charged to Income	28	1,290	22
Charged to Other Accounts	0	0	4
Deductions	5	1,290	4,291
Ending Balance	2,523	2,500	2,500
Loss carryforward tax valuation reserve
Consolidated Valuation and Qualifying Accounts
Beginning Balance	101,697	34,236	26,051
Charged to Income	23,663	67,461	(18,933)
Charged to Other Accounts	0	0	27,118
Deductions	0	0	0
Ending Balance	125,360	101,697	34,236
Loss carryforward tax valuation reserve | FES
Consolidated Valuation and Qualifying Accounts
Beginning Balance	15,810	11,650	9,290
Charged to Income	11,065	4,160	2,360
Charged to Other Accounts	0	0	0
Deductions	0	0	0
Ending Balance	$ 26,875	$ 15,810	$ 11,650