Noncontrolling Interests (Tables)

12 Months Ended

Dec. 31, 2012

Noncontrolling Interest [Abstract]

Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Table Text Block]

The following table summarizes changes in OGE Holdings' and the ArcLight group's membership interest in Enogex Holdings in 2012.

(In millions)	OGE Holdings		ArcLight group		Total
Balance at December 31, 2011 (units)	93.8		21.6		115.4
Ownership percentage at December 31, 2011	81.3	%	18.7	%	100.0	%
Issuance of 5,294,118 units of Enogex Holdings (A)	2.7		2.6		5.3
Balance at December 31, 2012 (units)	96.5		24.2		120.7
Ownership percentage at December 31, 2012	79.9	%	20.1	%	100.0	%

(A) EffectiveOctober 1, 2012, OGE Energy and the ArcLight group made contributions to Enogex Holdings of$45.0 millioneach to fund a portion of Enogex LLC's 2012capital requirements.

Changes in OGE Energy's Equity Attributable to Noncontrolling Interest [Table Text Block]

The following table summarizes changes in OGE Energy's equity which represents changes in additional paid-in capital for unrecognized gains from the issuance of equity interests in Enogex Holdings to the ArcLight group in 2012.

(In millions)
Net income attributable to OGE Energy	$	355.0
Transfers from the noncontrolling interest
Increase in paid-in capital for issuance of 5,294,118 units of Enogex Holdings (net of tax of $3.2 million)	5.1
Net transfers from the noncontrolling interest	5.1
Total of net income attributable to OGE Energy and transfers from noncontrolling interest	$	360.1

Schedule of Distributions Made to Members or Limited Partners, by Distribution [Table Text Block]

The following table summarizes the quarterly distributions in 2012.

(In millions)	OGE Holdings' Portion		ArcLight group's Portion		Total Distribution
First quarter 2012	$	24.4	$	5.6	$	30.0
Second quarter 2012	10.1		2.4		12.5
Third quarter 2012	10.2		2.3		12.5
Fourth quarter 2012	10.2		2.3		12.5
Total	$	54.9	$	12.6	$	67.5