Noncontrolling Interest Owner (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended								12 Months Ended				12 Months Ended						12 Months Ended											12 Months Ended
	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Sep. 30, 2010	Jun. 30, 2010	Mar. 31, 2010	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Feb. 01, 2011	Dec. 31, 2011 OGE Holdings [Member]	Dec. 31, 2011 Enogex Holdings [Member] units	Nov. 01, 2011 Enogex Holdings [Member] units	Oct. 03, 2011 Enogex Holdings [Member] units	Feb. 01, 2011 Enogex Holdings [Member] units	Dec. 31, 2010 Enogex Holdings [Member] units	Dec. 31, 2011 ArcLight Group [Member]	Dec. 31, 2011 OGE Holdings [Member] units	Nov. 01, 2011 OGE Holdings [Member]	Oct. 03, 2011 OGE Holdings [Member]	Feb. 01, 2011 OGE Holdings [Member]	Dec. 31, 2010 OGE Holdings [Member] units	Dec. 31, 2011 ArcLight Group [Member] units	Nov. 01, 2011 ArcLight Group [Member]	Oct. 03, 2011 ArcLight Group [Member]	Feb. 01, 2011 ArcLight Group [Member]	Dec. 31, 2010 ArcLight Group [Member] units	Dec. 31, 2011 Equity Issuance [Member]	Dec. 31, 2011 Equity Issuance [Member] Enogex Holdings [Member]		Dec. 31, 2011 Equity Issuance [Member] OGE Holdings [Member]		Dec. 31, 2011 Equity Issuance [Member] ArcLight Group [Member]		Dec. 31, 2011 Issuance 1 [Member]	Dec. 31, 2011 Issuance 1 [Member] Enogex Holdings [Member]		Dec. 31, 2011 Issuance 1 [Member] OGE Holdings [Member]		Dec. 31, 2011 Issuance 1 [Member] ArcLight Group [Member]		Dec. 31, 2011 Issuance 2 [Member]	Dec. 31, 2011 Issuance 2 [Member] Enogex Holdings [Member]		Dec. 31, 2011 Issuance 2 [Member] OGE Holdings [Member]		Dec. 31, 2011 Issuance 2 [Member] ArcLight Group [Member]		Dec. 31, 2011 Issuance 3 [Member]	Dec. 31, 2011 Issuance 3 [Member] Enogex Holdings [Member]		Dec. 31, 2011 Issuance 3 [Member] OGE Holdings [Member]		Dec. 31, 2011 Issuance 3 [Member] ArcLight Group [Member]
Changes in Ownership Interest [Line Items]
Proceeds from (Payments to) Noncontrolling Interests													$ 70.9						$ 214.6
Noncontrolling Interest Increase from Equity Issuance																															0	[1]	(0.1)	[1]	0.1	[1]		4.3	[2]	0.4	[2]	3.9	[2]		5.4	[3]	0.5	[3]	4.9	[3]		5.7	[4]	2.9	[4]	2.8	[4]
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Period Start, Total Ownership Percentage																																																				100.00%
Beginning period, balance														115,400,000				100,000,000		93,800,000				90,100,000	21,600,000				9,900,000
Ownership percentage, OGE Holdings, at beginning of period																				81.30%				90.10%
Ownership percentage, ArcLight Group, at beginning of period																									18.70%				9.90%
Ending period, balance														115,400,000				100,000,000		93,800,000				90,100,000	21,600,000				9,900,000
Ownership percentage, OGE Holdings, at end of period																				81.30%				90.10%
Ownership Percentage, ArcLight Group, at end of period																									18.70%				9.90%
Ending Period, Total Ownership Percentage																																																				100.00%
Percentage of Subsidiary Sold to Noncontrolling Interest												0.10%
Proceeds of Percentage of Subsidiary Sold to Noncontrolling Interest												1.9
Contributions Towards Meeting 2011 Capital Requirements																					52.9	10.0	8.0			53.0	90.0	71.6
Net Income Attributable to OGE Energy	36.4	178.7	103.0	24.8	30.7	163.1	77.3	24.2	342.9	295.3	258.3
Changes In Oge Energys Equity Attributable To Changes In Ownership Interest [Abstract]
Increase in paid-in capital for sale of 100,000 units of Enogex Holdings									45.5																					0.5							17.3							19.5							8.2
Limited Liability Corp Units Sold																	100,000
Limited Liability Corp Units Issued															5,725,190	5,405,405	4,303,007
Change from net income attributable to OGE Energy and transfers from noncontrolling interest									388.4
Consolidation Less than Wholly Owned Subsidiary, Parent Ownership Interest, Changes Issuance os Equity by Subsidiary to Noncontrolling Interest, Tax Effect																														$ 0.3							$ 10.9							$ 12.3							$ 5.2

[1] On February 1, 2011, OGE Energy sold a 0.1 percent membership interest in Enogex Holdings to the ArcLight group for $1.9 million

[2] On February 1, 2011, OGE Energy and the ArcLight group made contributions of $8.0 million and $71.6 million, respectively, to fund a portion of Enogex LLC's 2011 capital requirements

[3] On October 3, 2011, OGE Energy and the ArcLight group made contributions of $10.0 million and $90.0 million, respectively, to fund a portion of Enogex LLC's 2011 capital requirements

[4] On November 1, 2011, OGE Energy and the ArcLight group made contributions of $52.9 million and $53.0 million, respectively, to fund Enogex's gas gathering acquisitions as discussed in Note 3