Quarterly Financial Data

12 Months Ended

Dec. 31, 2012

Quarterly Financial Data [Abstract]

Quarterly Financial Information [Text Block]

Quarterly Financial Data (Unaudited)

Due to the seasonal fluctuations and other factors of the Company's businesses, the operating results for interim periods are not necessarily indicative of the results that may be expected for the year.In the Company's opinion, the following quarterly financial data includes all adjustments, consisting of normal recurring adjustments, necessary to fairly present such amounts.Summarized consolidated quarterly unaudited financial data is as follows:

Quarter ended (In millions, except per share data)		March 31		June 30		September 30		December 31		Total
Operating revenues	2012	$	840.7	$	855.0	$	1,113.4	$	862.1	$	3,671.2
	2011	$	840.5	$	978.1	$	1,212.1	$	885.2	$	3,915.9
Operating income	2012	$	98.3	$	177.3	$	304.0	$	97.3	$	676.9
	2011	$	67.9	$	182.2	$	299.7	$	96.9	$	646.7
Net income	2012	$	47.5	$	101.6	$	192.4	$	43.5	$	385.0
	2011	$	29.7	$	109.3	$	181.4	$	43.2	$	363.6
Net income attributable to OGE Energy	2012	$	37.1	$	93.9	$	185.5	$	38.5	$	355.0
	2011	$	24.8	$	103.0	$	178.7	$	36.4	$	342.9
Basic earnings per average common share attributable to OGE Energy common shareholders (A)	2012	$	0.38	$	0.95	$	1.88	$	0.39	$	3.60
	2011	$	0.25	$	1.05	$	1.82	$	0.37	$	3.50
Diluted earnings per average common share attributable to OGE Energy common shareholders (A)	2012	$	0.38	$	0.95	$	1.87	$	0.39	$	3.58
	2011	$	0.25	$	1.04	$	1.80	$	0.37	$	3.45

(A) Due to the impact of dilution on the earnings per share calculation, quarterly earnings per share amounts may not add to the total.