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Pension and Postretirement Health and Life Benefits (Tables)

12 Months Ended

Dec. 31, 2011

Pension and Postretirement Health and Life Benefits

Schedule of Changes in Projected Benefit Obligations [Table Text Block]

		Defined Benefit Pension Plans								Postretirement Health and Life Benefit Plans
		Years Ended December 31,								Years Ended December 31,
Changes in Benefit Obligations:		2011				2010				2011				2010
Obligations at beginning of year		$	876.8			$	840.0			$	230.6			$	219.3
Actuarial (gains) losses, net			93.4				10.3				14.7				5.0
Service costs			16.2				19.3				4.3				5.0
Interest costs			50.3				48.9				12.2				11.9
Gross benefits paid			(50.4	)			(41.7	)			(11.5	)			(10.8	)
Less federal subsidy on benefits paid			-				-				0.7				0.2
Curtailment losses			3.2				-				1.9				-
Obligations at end of year			989.5				876.8				252.9				230.6
Changes in Plan Assets:
Fair value of plan assets at beginning of year			728.5				661.7				51.9				50.4
Actual return on plan assets			34.1				95.7				(1.8	)			5.4
USEC contributions			15.6				12.8				6.5				6.9
Benefits paid			(50.4	)			(41.7	)			(11.5	)			(10.8	)
Fair value of plan assets at end of year			727.8				728.5				45.1				51.9
(Unfunded) status at end of year			(261.7	)			(148.3	)			(207.8	)			(178.7	)
Amounts recognized in assets and liabilities:
Current liabilities		$	(3.4	)		$	(2.9	)		$	-			$	-
Noncurrent liabilities			(258.3	)			(145.4	)			(207.8	)			(178.7	)
		$	(261.7	)		$	(148.3	)		$	(207.8	)		$	(178.7	)
Amounts recognized in accumulated other comprehensive income, pre-tax:
Net actuarial loss		$	280.5			$	176.7			$	59.9			$	43.6
Prior service cost (credit)			3.2				4.8				-				0.1
		$	283.7			$	181.5			$	59.9			$	43.7

Schedule of Net Benefit Costs

		Defined Benefit Pension Plans												Postretirement Health and Life Benefit Plans
(in millions)		Years Ended December 31,												Years Ended December 31,
		2011				2010				2009				2011				2010				2009
Net Periodic Benefit Costs
Service costs		$	16.2			$	19.3			$	18.7			$	4.3			$	5.0			$	4.6
Interest costs			50.3				48.9				47.7				12.2				11.9				12.6
Expected return on plan assets (gains)			(54.0	)			(48.7	)			(42.6	)			(3.7	)			(3.6	)			(3.0	)
Amortization of prior service costs (credits)			1.7				1.8				1.7				-				(8.5	)			(14.4	)
Amortization of actuarial (gains) losses, net			9.4				16.0				23.9				2.6				2.7				4.2
Curtailment losses			3.2				0.4				-				1.9				-				-
Net periodic benefit costs		$	26.8			$	37.7			$	49.4			$	17.3			$	7.5			$	4.0
Other Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Income
Net (gain) loss		$	115.4			$	(36.7	)		$	(48.7	)		$	20.8			$	3.2			$	(7.8	)
Prior service costs			-				-				1.3				-				-				0.2
Amortization of actuarial (gains) losses, net			(11.6	)			(16.0	)			(23.9	)			(4.6	)			(2.7	)			(4.2	)
Amortization of prior service costs (credits)			(1.6	)			(2.2	)			(1.7	)			-				8.5				14.4
Total (gain) loss recognized in other comprehensive income, pre-tax		$	102.2			$	(54.9	)		$	(73.0	)		$	16.2			$	9.0			$	2.6
Total (gain) loss recognized in net periodic benefit costs (income) and other comprehensive income, pre-tax		$	129.0			$	(17.2	)		$	(23.6	)		$	33.5			$	16.5			$	6.6

Schedule of Assumptions Used [Table Text Block]

Assumptions used to determine net periodic benefit costs:
Discount rate			5.77	%			5.84	%			6.09	%			5.32	%			5.44	%			6.00	%
Expected return on plan assets			7.50				7.50				7.75				7.50				7.50				7.50
Compensation increases			4.25				4.25				4.25				4.25				4.25				4.25

Schedule of Health Care Cost Trend Rates [Table Text Block]

		December 31,
		2011				2010
Healthcare cost trend rate for the following year			8.00	%			8.00	%
Long-term rate that the healthcare cost trend rate gradually declines to			5	%			5	%
Year that the healthcare cost trend rate is expected to reach the long-term rate			2018				2018

Schedule of Effect of One-Percentage-Point Change in Assumed Health Care Cost Trend Rates [Table Text Block]

		One Percentage Point
		Increase				Decrease
Postretirement health benefit obligation		$	8.5			$	(8.0	)
Net periodic benefit costs		$	1.0			$	(0.9	)

Schedule of Allocation of Plan Assets [Table Text Block]

		Percentage of Plan Assets								Target Allocation
		December 31,								Range
		2011				2010				2012
Defined Benefit Pension Plans:
Equity securities			50	%			54	%			40 -				60	%
Debt securities			50				46				40 -				60
			100	%			100	%
Postretirement Health and Life Benefit Plans:
Equity securities			69	%			67	%			55 -				75	%
Debt securities			31				33				25 -				45
			100	%			100	%

Schedule of Fair Value of Pension Plan Assets

		Defined Benefit Pension Plans
		Level 1				Level 2				Level 3				Total
U.S. government securities		$	-			$	70.1			$	-			$	70.1
Collective trust – money market funds			-				21.4				-				21.4
Collective trust – bond funds			-				41.5				-				41.5
Collective trust – equity funds			-				362.9				-				362.9
Preferred equity			0.3				-				-				0.3
Corporate debt			-				218.1				0.9				219.0
Municipal bonds			-				7.2				-				7.2
Mortgage and asset backed securities			-				0.8				-				0.8
Fair value of investments by hierarchy level		$	0.3			$	722.0			$	0.9			$	723.2
Accrued interest receivable															4.2
Unsettled transactions receivable															0.4
Plan assets at December 31, 2011														$	727.8

Schedule of Fair Value of Postretirement Benefit Plan Assets

		Postretirement Health and Life Benefit Plans
		Level 1				Level 2				Level 3				Total
Money market funds		$	1.2			$	-			$	-			$	1.2
Bond mutual funds			14.4				-				-				14.4
Equity mutual funds			29.5				-				-				29.5
Fair value of investments by hierarchy level		$	45.1			$	-			$	-			$	45.1

Reconciliation of Fair Value of Assets Using Unobservable Inputs

		Corporate Debt
Beginning balance		$	-
Transfer in to Level 3			0.9
Net investment gain (loss)			-
Ending balance		$	0.9

Schedule of Estimated Future Benefit Payments

		Defined Benefit Pension Plans				Postretirement Health and Life Benefit Plans				Expected Subsidies From Medicare
2012		$	58.1			$	15.6			$	0.5
2013			69.8				17.0				0.7
2014			58.7				18.3				0.9
2015			59.1				20.4				1.1
2016			59.5				23.5				1.4
2017 to 2021			307.8				125.4				9.7

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