Summary of Significant Accounting Policies Property, Plant and Equipment (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 9,651.6		$ 11,891.9
Accumulated Depreciation	2,978.8		3,547.1
Property, Plant and Equipment, Net	6,672.8		8,344.8
Proceeds from insurance	0		7.6		7.4
Gain on insurance proceeds	0		(7.5)		(3.0)
Capitalized Computer Software, Gross	24.0		33.1
Capitalized Computer Software, Amortization	11.2		14.1		9.2
McClain Plant [Member]
Property, Plant and Equipment [Line Items]
Jointly Owned Utility Plant, Ownership Amount of Construction Work in Progress	0.1		0.1
Jointly Owned Utility Plant, Proportionate Ownership Share	77.00%	[1]	77.00%	[2]
Property, Plant and Equipment, Gross	180.8	[1]	182.1	[2]
Accumulated Depreciation	62.1	[1]	56.3	[2]
Property, Plant and Equipment, Net	118.7	[1]	125.8	[2]
Redbud Plant [Member]
Property, Plant and Equipment [Line Items]
Jointly Owned Utility Plant, Ownership Amount of Construction Work in Progress	39.5		0.3
Jointly Owned Utility Plant, Proportionate Ownership Share	51.00%	[1],[3]	51.00%	[2],[4]
Property, Plant and Equipment, Gross	498.9	[1],[3]	458.5	[2],[4]
Accumulated Depreciation	89.7	[1],[3]	69.5	[2],[4]
Property, Plant and Equipment, Net	409.2	[1],[3]	389.0	[2],[4]
Amount of Acquisition Adjustments	148.3		148.3
Public Utilities, Property, Plant and Equipment, Amount of Acquisition Adjustments, Related Accumulated Depreciation	28.8		23.3
OGE Energy [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	152.4		142.1
Accumulated Depreciation	114.2		103.2
Property, Plant and Equipment, Net	38.2		38.9
Capitalized Computer Software, Gross	7.2		11.6
Capitalized Computer Software, Amortization	6.4		6.8		6.4
OGE Energy [Member] | Total Property Plant and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	152.4		142.1
Accumulated Depreciation	114.2		103.2
Property, Plant and Equipment, Net	38.2		38.9
Og and E [Member]
Property, Plant and Equipment [Line Items]
Capitalized Computer Software, Gross	16.8		17.6
Capitalized Computer Software, Amortization	4.0		4.2		1.8
Og and E [Member] | Total Property Plant and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	9,499.2		8,749.7
Accumulated Depreciation	2,864.6		2,705.6
Property, Plant and Equipment, Net	6,634.6		6,044.1
Og and E [Member] | Electric Transmission and Distribution [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	3,403.8		3,222.7
Accumulated Depreciation	1,028.2		969.6
Property, Plant and Equipment, Net	2,375.6		2,253.1
Og and E [Member] | Electric Generation Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	3,551.0	[5]	3,446.6	[6]
Accumulated Depreciation	1,306.1	[5]	1,242.4	[6]
Property, Plant and Equipment, Net	2,244.9	[5]	2,204.2	[6]
Amount of Acquisition Adjustments	148.3		148.3
Public Utilities, Property, Plant and Equipment, Amount of Acquisition Adjustments, Related Accumulated Depreciation	28.8		23.3
Og and E [Member] | Transmission Equipment [Member]
Property, Plant and Equipment [Line Items]
Amount of Acquisition Adjustments	3.3		3.3
Amount of Acquistion Adjustments Related Accumulated Amortization	0.3		0.3
Og and E [Member] | Electric Transmission [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	2,163.7	[7]	1,712.6	[7]
Accumulated Depreciation	385.0	[7]	359.8	[7]
Property, Plant and Equipment, Net	1,778.7	[7]	1,352.8	[7]
Og and E [Member] | Finite-Lived Intangible Assets, Major Class Name [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	50.5		50.2
Accumulated Depreciation	27.1		25.0
Property, Plant and Equipment, Net	23.4		25.2
Og and E [Member] | Property, Plant and Equipment, Other Types [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	330.2		317.6
Accumulated Depreciation	118.2		108.8
Property, Plant and Equipment, Net	212.0		208.8
Enogex [Member]
Property, Plant and Equipment [Line Items]
Capitalized Computer Software, Gross	0		3.9
Capitalized Computer Software, Amortization	0.8		3.1		1.0
Enogex [Member] | Total Property Plant and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross			3,000.1
Accumulated Depreciation			738.3
Property, Plant and Equipment, Net			2,261.8
Enogex [Member] | Transportation and Storage [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross			988.6
Accumulated Depreciation			292.7
Property, Plant and Equipment, Net			695.9
Enogex [Member] | Gas Gathering and Processing Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross			2,011.5
Accumulated Depreciation			445.6
Property, Plant and Equipment, Net			$ 1,565.9

[1] Construction work in progress was $0.1 million and $39.5 million for the McClain and Redbud Plants, respectively.

[2] Construction work in progress was $0.1 million and $0.3 million for the McClain and Redbud Plants, respectively.

[3] This amount includes a plant acquisition adjustment of $148.3 million and accumulated amortization of $28.8 million.

[4] This amount includes a plant acquisition adjustment of $148.3 million and accumulated amortization of $23.3 million.

[5] This amount includes a plant acquisition adjustment of $148.3 million and accumulated amortization of $28.8 million.

[6] This amount includes a plant acquisition adjustment of $148.3 million and accumulated amortization of $23.3 million.

[7] This amount includes a plant acquisition adjustment of $3.3 million and accumulated amortization of $0.3 million.