Short-Term Debt and Credit Facilities (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015
Line of Credit Facility [Line Items]
Short-term debt		$ 236.2	$ 0.0
Line of Credit Facility [Abstract]
Aggregate Commitment		1,150.0
Amount Outstanding	[1]	$ 238.0
Weighted Average Interest Rate		0.95%
OGE Energy [Member]
Line of Credit Facility [Abstract]
Aggregate Commitment	[2]	$ 750.0
Amount Outstanding	[2]	$ 236.2
Weighted Average Interest Rate	[2],[3]	0.95%
Maturity	[2],[4]	Dec. 13, 2018
OG&E [Member]
Line of Credit Facility [Abstract]
Aggregate Commitment	[5]	$ 400.0
Letters of Credit Outstanding, Amount	[5]	$ 1.8
Weighted Average Interest Rate	[3],[5]	0.95%
Maturity	[4],[5]	Dec. 13, 2018
Period For Which Regulatory Approval Has Been Given to Acquire Short Term Debt		2 years
Short Term Borrowing Capacity That Has Regulatory Approval		$ 800.0

[1] Includes direct borrowings under the revolving credit agreements, commercial paper borrowings and letters of credit at December 31, 2016.

[2] This bank facility is available to back up OGE Energy's commercial paper borrowings and to provide revolving credit borrowings. This bank facility can also be used as a letter of credit facility.

[3] Represents the weighted-average interest rate for the outstanding borrowings under the revolving credit agreements, commercial paper borrowings and letters of credit.

[4] In December 2011, OGE Energy and OG&E entered into unsecured revolving credit agreements in the aggregate of $1,150.0 million ($750.0 million for OGE Energy and $400.0 million for OG&E) which expire in December 2018. OGE Energy and OG&E expect to replace the existing agreements with new revolving credit agreements during 2017, under terms and conditions generally similar to the existing agreements.

[5] This bank facility is available to back up OG&E's commercial paper borrowings and to provide revolving credit borrowings. This bank facility can also be used as a letter of credit facility.