Retirement Plans and Postretirement Benefit Plans (Tables)

9 Months Ended

Sep. 30, 2011

Defined Benefit Pension Plans and Defined Benefit Postretirement Plans Disclosure [Abstract]

Schedule of Defined Benefit Plans Disclosures [Table Text Block]

The details of net periodic benefit cost of the Company's Pension Plan, the Restoration of Retirement Income Plan and the postretirement benefit plans included in the Condensed Consolidated Financial Statements are as follows:

Net Periodic Benefit Cost

	Pension Plan
	Three Months Ended						Nine Months Ended
	September 30,						September 30,
(In millions)	2011 (A)			2010 (A)			2011 (B)			2010 (B)
Service cost	$	4.4		$	4.1		$	13.2		$	12.5
Interest cost	8.4			8.0			25.0			23.9
Expected return on plan assets	(11.4		)	(10.6		)	(34.1		)	(31.8		)
Amortization of net loss	4.8			5.3			14.4			15.9
Amortization of unrecognized prior service cost	0.6			0.6			1.8			1.8
Net periodic benefit cost	$	6.8		$	7.4		$	20.3		$	22.3

	Restoration of Retirement Income Plan
	Three Months Ended				Nine Months Ended
	September 30,				September 30,
(In millions)	2011 (A)		2010 (A)		2011 (B)		2010 (B)
Service cost	$	0.3	$	0.3	$	0.8	$	0.7
Interest cost	0.1		0.2		0.4		0.4
Amortization of net loss	0.1		—		0.3		0.2
Amortization of unrecognized prior service cost	0.1		0.1		0.5		0.5
Net periodic benefit cost	$	0.6	$	0.6	$	2.0	$	1.8

(A) In addition to the $7.4 million and $8.0 million of net periodic benefit cost recognized during the three months ended September 30, 2011 and 2010, respectively, OG&E recognized an increase in pension expense during the three months ended September 30, 2011 and 2010 of $2.7 million and $2.3 million, respectively, to maintain the allowable amount to be recovered for pension expense in the Oklahoma jurisdiction which are included in the Pension tracker regulatory liability (see Note 1).

(B) In addition to the $22.3 million and $24.1 million of net periodic benefit cost recognized during the nine months ended September 30, 2011 and 2010, respectively, OG&E recognized an increase in pension expense during the nine months ended September 30, 2011 and 2010 of $8.0 million and $5.8 million, respectively, to maintain the allowable amount to be recovered for pension expense in the Oklahoma jurisdiction which are included in the Pension tracker regulatory liability (see Note 1).

	Postretirement Benefit Plans
	Three Months Ended						Nine Months Ended
	September 30,						September 30,
(In millions)	2011 (C)			2010			2011 (C)			2010
Service cost	$	0.8		$	1.1		$	2.6		$	3.2
Interest cost	3.2			4.2			9.4			12.7
Expected return on plan assets	(1.2		)	(1.7		)	(3.8		)	(5.2		)
Amortization of transition obligation	0.7			0.7			2.1			2.1
Amortization of net loss	4.6			3.0			13.7			9.1
Amortization of unrecognized prior service cost	(4.2		)	—			(12.4		)	—
Net periodic benefit cost	$	3.9		$	7.3		$	11.6		$	21.9

(C) In addition to the $3.9 million and $11.6 million of net periodic benefit cost recognized during the three and nine months ended September 30, 2011, respectively, OG&E recognized an increase in postretirement medical expense during the three and nine months ended September 30, 2011 of $0.8 million and $2.5 million, respectively, to maintain the allowable amount to be recovered for postretirement medical expense in the Oklahoma jurisdiction which are included in the Pension tracker regulatory liability (see Note 1).