Annual report pursuant to Section 13 and 15(d)

Postretirement Benefits (Details)

v2.4.0.6
Postretirement Benefits (Details) (USD $)
In Millions, unless otherwise specified
 12 Months Ended
Dec. 31, 2012
Dec. 31, 2011
Dec. 31, 2010
Defined Benefit Plan Disclosure [Line Items]      
Defined contribution plan expense $ 34.2 $ 30.9 $ 25.0
Contributions to multiemployer plans 0.6 0.5 0.3
Reductions of benefit obligations due to negative plan amendments 0.2 6.1  
Change in Benefit Obligations [Roll Forward]      
Plan amendments (0.2) (6.1)  
Change in Plan Assets [Roll Forward]      
Fair value of plan assets at previous December 31 795.7 [1]    
Fair value of plan assets at December 31 898.6 [2] 795.7 [1]  
Pension Plans with Accumulated Benefit Obligations in Excess of Plan Assets [Abstract]      
Projected benefit obligation 1,388.0 1,319.3  
Accumulated benefit obligation 1,388.0 1,319.3  
Fair value of plan assets 898.6 795.7  
Funded status 65.00% 60.00%  
Unfunded, nonqualified pension plan projected and accumulated benefit obligations included in funded status of the Company's pension plans 42.3 43.1  
Net Actuarial Losses [Abstract]      
Percentage of benefit obligation or market value of assets, over which actuarial gains and losses are subject to amortization (in hundredths) 10.00%    
Defined Benefit Plan, Assumed Health Care Cost Trend Rates [Abstract]      
Health care cost trend rate for next year 7.50% 7.60%  
Rate to which the cost trend rate is assumed to decline (the ultimate trend rate) 4.50% 4.50%  
Year rate reaches the ultimate trend rate 2028 2028  
Defined Benefit Plan, Effect of One-Percentage Point Change in Assumed Health Care Cost Trend Rates [Abstract]      
Effect on total service and interest cost, increase 0    
Effect on accumulated postretirement benefit obligation, increase 0.5    
Effect on total service and interest cost, decrease 0    
Effect on accumulated postretirement benefit obligation, decrease (0.5)    
Defined Benefit Plan, Actual Plan Asset Allocations [Abstract]      
Total 100.00% 100.00%  
Defined Benefit Plan, Assets, Target Allocations [Abstract]      
Total 100.00%    
Fair value of plan assets 898.6 [2] 795.7 [1]  
Expected Benefit Payments [Abstract]      
Amortization of prior service costs (credits) for former/inactive employees 1.3 1.3  
Fair Value, Inputs, Level 1 [Member]
      
Change in Plan Assets [Roll Forward]      
Fair value of plan assets at December 31 102.8 [2] 75.7 [1]  
Defined Benefit Plan, Assets, Target Allocations [Abstract]      
Fair value of plan assets 102.8 [2] 75.7 [1]  
Fair Value, Inputs, Level 2 [Member]
      
Change in Plan Assets [Roll Forward]      
Fair value of plan assets at December 31 794.7 [2] 724.4 [1]  
Defined Benefit Plan, Assets, Target Allocations [Abstract]      
Fair value of plan assets 794.7 [2] 724.4 [1]  
Fair Value, Inputs, Level 3 [Member]
      
Change in Plan Assets [Roll Forward]      
Fair value of plan assets at December 31 0 [2] 0 [1]  
Defined Benefit Plan, Assets, Target Allocations [Abstract]      
Fair value of plan assets 0 [2] 0 [1]  
Fair Value [Member]
      
Change in Plan Assets [Roll Forward]      
Fair value of plan assets at December 31 897.5 [2] 800.1 [1]  
Defined Benefit Plan, Assets, Target Allocations [Abstract]      
Fair value of plan assets 897.5 [2] 800.1 [1]  
Short-term Investments [Member]
      
Defined Benefit Plan, Actual Plan Asset Allocations [Abstract]      
Total 7.00% 4.00%  
Defined Benefit Plan, Assets, Target Allocations [Abstract]      
Total 0.00%    
Short-term Investments [Member] | Fair Value, Inputs, Level 1 [Member]
      
Change in Plan Assets [Roll Forward]      
Fair value of plan assets at December 31 0.1 [2] 0.1 [1]  
Defined Benefit Plan, Assets, Target Allocations [Abstract]      
Fair value of plan assets 0.1 [2] 0.1 [1]  
Short-term Investments [Member] | Fair Value, Inputs, Level 2 [Member]
      
Change in Plan Assets [Roll Forward]      
Fair value of plan assets at December 31 61.9 [2] 28.8 [1]  
Defined Benefit Plan, Assets, Target Allocations [Abstract]      
Fair value of plan assets 61.9 [2] 28.8 [1]  
Short-term Investments [Member] | Fair Value, Inputs, Level 3 [Member]
      
Change in Plan Assets [Roll Forward]      
Fair value of plan assets at December 31 0 [2] 0 [1]  
Defined Benefit Plan, Assets, Target Allocations [Abstract]      
Fair value of plan assets 0 [2] 0 [1]  
Short-term Investments [Member] | Fair Value [Member]
      
Change in Plan Assets [Roll Forward]      
Fair value of plan assets at December 31 62.0 [2] 28.9 [1]  
Defined Benefit Plan, Assets, Target Allocations [Abstract]      
Fair value of plan assets 62.0 [2] 28.9 [1]  
United States Equity Securities [Member]
      
Defined Benefit Plan, Actual Plan Asset Allocations [Abstract]      
Total 37.00% 46.00%  
Defined Benefit Plan, Assets, Target Allocations [Abstract]      
Total 38.00%    
United States Equity Securities [Member] | Fair Value, Inputs, Level 1 [Member]
      
Change in Plan Assets [Roll Forward]      
Fair value of plan assets at December 31 0 [2],[3] 0 [1],[4]  
Defined Benefit Plan, Assets, Target Allocations [Abstract]      
Fair value of plan assets 0 [2],[3] 0 [1],[4]  
United States Equity Securities [Member] | Fair Value, Inputs, Level 2 [Member]
      
Change in Plan Assets [Roll Forward]      
Fair value of plan assets at December 31 336.7 [2],[3] 367.2 [1],[4]  
Defined Benefit Plan, Assets, Target Allocations [Abstract]      
Fair value of plan assets 336.7 [2],[3] 367.2 [1],[4]  
United States Equity Securities [Member] | Fair Value, Inputs, Level 3 [Member]
      
Change in Plan Assets [Roll Forward]      
Fair value of plan assets at December 31 0 [2],[3] 0 [1],[4]  
Defined Benefit Plan, Assets, Target Allocations [Abstract]      
Fair value of plan assets 0 [2],[3] 0 [1],[4]  
United States Equity Securities [Member] | Fair Value [Member]
      
Change in Plan Assets [Roll Forward]      
Fair value of plan assets at December 31 336.7 [2],[3] 367.2 [1],[4]  
Defined Benefit Plan, Assets, Target Allocations [Abstract]      
Fair value of plan assets 336.7 [2],[3] 367.2 [1],[4]  
International Equity Securities [Member]
      
Defined Benefit Plan, Actual Plan Asset Allocations [Abstract]      
Total 7.00% 8.00%  
Defined Benefit Plan, Assets, Target Allocations [Abstract]      
Total 7.00%    
International Equity Securities [Member] | Fair Value, Inputs, Level 1 [Member]
      
Change in Plan Assets [Roll Forward]      
Fair value of plan assets at December 31 0 [2],[3] 0 [1],[4]  
Defined Benefit Plan, Assets, Target Allocations [Abstract]      
Fair value of plan assets 0 [2],[3] 0 [1],[4]  
International Equity Securities [Member] | Fair Value, Inputs, Level 2 [Member]
      
Change in Plan Assets [Roll Forward]      
Fair value of plan assets at December 31 60.6 [2],[3] 65.4 [1],[4]  
Defined Benefit Plan, Assets, Target Allocations [Abstract]      
Fair value of plan assets 60.6 [2],[3] 65.4 [1],[4]  
International Equity Securities [Member] | Fair Value, Inputs, Level 3 [Member]
      
Change in Plan Assets [Roll Forward]      
Fair value of plan assets at December 31 0 [2],[3] 0 [1],[4]  
Defined Benefit Plan, Assets, Target Allocations [Abstract]      
Fair value of plan assets 0 [2],[3] 0 [1],[4]  
International Equity Securities [Member] | Fair Value [Member]
      
Change in Plan Assets [Roll Forward]      
Fair value of plan assets at December 31 60.6 [2],[3] 65.4 [1],[4]  
Defined Benefit Plan, Assets, Target Allocations [Abstract]      
Fair value of plan assets 60.6 [2],[3] 65.4 [1],[4]  
Fixed Income Securities [Member]
      
Defined Benefit Plan, Actual Plan Asset Allocations [Abstract]      
Total 49.00% 42.00%  
Defined Benefit Plan, Assets, Target Allocations [Abstract]      
Total 55.00%    
Government Fixed-Income Securities [Member] | Fair Value, Inputs, Level 1 [Member]
      
Change in Plan Assets [Roll Forward]      
Fair value of plan assets at December 31 102.7 [2],[5] 75.6 [1],[5]  
Defined Benefit Plan, Assets, Target Allocations [Abstract]      
Fair value of plan assets 102.7 [2],[5] 75.6 [1],[5]  
Government Fixed-Income Securities [Member] | Fair Value, Inputs, Level 2 [Member]
      
Change in Plan Assets [Roll Forward]      
Fair value of plan assets at December 31 43.8 [2],[5] 38.0 [1],[5]  
Defined Benefit Plan, Assets, Target Allocations [Abstract]      
Fair value of plan assets 43.8 [2],[5] 38.0 [1],[5]  
Government Fixed-Income Securities [Member] | Fair Value, Inputs, Level 3 [Member]
      
Change in Plan Assets [Roll Forward]      
Fair value of plan assets at December 31 0 [2],[5] 0 [1],[5]  
Defined Benefit Plan, Assets, Target Allocations [Abstract]      
Fair value of plan assets 0 [2],[5] 0 [1],[5]  
Government Fixed-Income Securities [Member] | Fair Value [Member]
      
Change in Plan Assets [Roll Forward]      
Fair value of plan assets at December 31 146.5 [2],[5] 113.6 [1],[5]  
Defined Benefit Plan, Assets, Target Allocations [Abstract]      
Fair value of plan assets 146.5 [2],[5] 113.6 [1],[5]  
Corporate Fixed-Income Securities [Member] | Fair Value, Inputs, Level 1 [Member]
      
Change in Plan Assets [Roll Forward]      
Fair value of plan assets at December 31 0 [2],[6] 0 [1],[6]  
Defined Benefit Plan, Assets, Target Allocations [Abstract]      
Fair value of plan assets 0 [2],[6] 0 [1],[6]  
Corporate Fixed-Income Securities [Member] | Fair Value, Inputs, Level 2 [Member]
      
Change in Plan Assets [Roll Forward]      
Fair value of plan assets at December 31 117.5 [2],[6] 98.5 [1],[6]  
Defined Benefit Plan, Assets, Target Allocations [Abstract]      
Fair value of plan assets 117.5 [2],[6] 98.5 [1],[6]  
Corporate Fixed-Income Securities [Member] | Fair Value, Inputs, Level 3 [Member]
      
Change in Plan Assets [Roll Forward]      
Fair value of plan assets at December 31 0 [2],[6] 0 [1],[6]  
Defined Benefit Plan, Assets, Target Allocations [Abstract]      
Fair value of plan assets 0 [2],[6] 0 [1],[6]  
Corporate Fixed-Income Securities [Member] | Fair Value [Member]
      
Change in Plan Assets [Roll Forward]      
Fair value of plan assets at December 31 117.5 [2],[6] 98.5 [1],[6]  
Defined Benefit Plan, Assets, Target Allocations [Abstract]      
Fair value of plan assets 117.5 [2],[6] 98.5 [1],[6]  
Commingled Funds [Member] | Fair Value, Inputs, Level 1 [Member]
      
Change in Plan Assets [Roll Forward]      
Fair value of plan assets at December 31 0 [2],[7] 0 [1],[7]  
Defined Benefit Plan, Assets, Target Allocations [Abstract]      
Fair value of plan assets 0 [2],[7] 0 [1],[7]  
Commingled Funds [Member] | Fair Value, Inputs, Level 2 [Member]
      
Change in Plan Assets [Roll Forward]      
Fair value of plan assets at December 31 174.2 [2],[7] 126.5 [1],[7]  
Defined Benefit Plan, Assets, Target Allocations [Abstract]      
Fair value of plan assets 174.2 [2],[7] 126.5 [1],[7]  
Commingled Funds [Member] | Fair Value, Inputs, Level 3 [Member]
      
Change in Plan Assets [Roll Forward]      
Fair value of plan assets at December 31 0 [2],[7] 0 [1],[7]  
Defined Benefit Plan, Assets, Target Allocations [Abstract]      
Fair value of plan assets 0 [2],[7] 0 [1],[7]  
Commingled Funds [Member] | Fair Value [Member]
      
Change in Plan Assets [Roll Forward]      
Fair value of plan assets at December 31 174.2 [2],[7] 126.5 [1],[7]  
Defined Benefit Plan, Assets, Target Allocations [Abstract]      
Fair value of plan assets 174.2 [2],[7] 126.5 [1],[7]  
Other Pension Plan Assets [Member] | Fair Value [Member]
      
Change in Plan Assets [Roll Forward]      
Fair value of plan assets at December 31 1.1 [2],[8] (4.4) [1],[8]  
Defined Benefit Plan, Assets, Target Allocations [Abstract]      
Fair value of plan assets 1.1 [2],[8] (4.4) [1],[8]  
Pension Plans [Member]
      
Defined Benefit Plan Disclosure [Line Items]      
Reductions of benefit obligations due to negative plan amendments 0 0  
Net Periodic Benefit Cost [Abstract]      
Service cost 0.2 1.1 1.1
Interest cost 57.7 62.4 64.8
Expected return on plan assets (55.2) (53.3) (49.5)
Amortization of prior service costs (credits) 0 0.4 0.4
Amortization of net actuarial losses 21.9 21.3 22.2
Curtailment loss 0.1 0.3 0.1
Net pension and other benefit costs 24.7 32.2 39.1
Change in Benefit Obligations [Roll Forward]      
Benefit obligation at previous December 31 1,319.3 1,214.2  
Service cost 0.2 1.1 1.1
Interest cost 57.7 62.4 64.8
Participant contributions 0 0  
Actuarial losses (gains) 84.5 113.1  
Benefit payments (73.7) (71.5)  
Plan amendments 0 0  
Benefit obligation at December 31 1,388.0 1,319.3 1,214.2
Change in Plan Assets [Roll Forward]      
Fair value of plan assets at previous December 31 795.7 740.4  
Actual return on plan assets 107.6 47.2  
Employer contributions 69.0 79.6  
Participant contributions 0 0  
Benefit payments (73.7) (71.5)  
Fair value of plan assets at December 31 898.6 795.7 740.4
Funded status at December 31 (489.4) (523.6)  
Amounts Recognized in Consolidated Balance Sheet [Abstract]      
Accrued expenses 4.0 4.0  
Postretirement benefit liabilities 485.4 519.6  
Net amount recognized 489.4 523.6  
Prior Service Costs (Credits) [Abstract]      
Beginning balance 0.1 0.8  
Prior service costs (credits) arising during the period 0 0  
Amount recognized as component of net benefit costs (0.1) (0.7)  
Ending balance 0 0.1 0.8
Net Actuarial Losses [Abstract]      
Beginning balance 591.9 494.1  
Actuarial losses (gains) arising during the period 32.1 119.1  
Amount recognized as component of net benefit costs (21.9) (21.3)  
Ending balance 602.1 591.9 494.1
Total 602.1 592.0  
Estimated pretax prior service (cost) credit in accumulated other comprehensive income (loss) expected to be recognized over the next year 0    
Estimated pretax net actuarial loss in accumulated other comprehensive income (loss) expected to be recognized over the next year 21.4    
Defined Benefit Plan, Weighted average assumptions used to determine pension and other postretirement benefit obligations [Abstract]      
Discount rate 4.00% 4.50%  
Rate of compensation increase 0.00% [9] 0.00% [9]  
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]      
Discount rate (in hundredths) 4.50% [10]   5.85% [10]
Long-term rate of return on plan assets (in hundredths) 7.00% [11] 7.25% [11] 7.50% [11]
Rate of compensation increase (in hundredths) 0.00% [11] 0.00% [11] 0.00% [11]
Defined Benefit Plan, Assets, Target Allocations [Abstract]      
Fair value of plan assets 898.6 795.7 740.4
Expected Benefit Payments [Abstract]      
Company contributions expected to be made in 2013 54.0 [12]    
2013 78.5    
2014 80.1    
2015 81.5    
2016 82.4    
2017 83.3    
2018-2022 418.9    
Defined Benefit Plan Estimated Future Employer Required Contributions In Next Fiscal Year Qualified Plan 50.0    
Defined Benefit Plan Estimated Future Employer Contributions In Next Fiscal Year Unfunded Plan 4.0    
Pension Plans [Member] | Minimum [Member]
      
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]      
Discount rate (in hundredths)   5.20% [10]  
Pension Plans [Member] | Maximum [Member]
      
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]      
Discount rate (in hundredths)   5.30% [10]  
Other Postretirement Benefit Plans [Member]
      
Defined Benefit Plan Disclosure [Line Items]      
Reductions of benefit obligations due to negative plan amendments 0.2 6.1  
Net Periodic Benefit Cost [Abstract]      
Service cost 0 0.2 0.4
Interest cost 2.4 3.2 3.9
Expected return on plan assets 0 0 0
Amortization of prior service costs (credits) (6.3) (5.2) (3.9)
Amortization of net actuarial losses 0.7 1.0 0
Curtailment loss 0 0 0
Net pension and other benefit costs (3.2) (0.8) 0.4
Change in Benefit Obligations [Roll Forward]      
Benefit obligation at previous December 31 69.9 77.8  
Service cost 0 0.2 0.4
Interest cost 2.4 3.2 3.9
Participant contributions 1.3 1.7  
Actuarial losses (gains) (5.5) 2.8  
Benefit payments (9.9) (9.7)  
Plan amendments (0.2) (6.1)  
Benefit obligation at December 31 58.0 69.9 77.8
Change in Plan Assets [Roll Forward]      
Fair value of plan assets at previous December 31 0 0  
Actual return on plan assets 0 0  
Employer contributions 8.6 8.0  
Participant contributions 1.3 1.7  
Benefit payments (9.9) (9.7)  
Fair value of plan assets at December 31 0 0 0
Funded status at December 31 (58.0) (69.9)  
Amounts Recognized in Consolidated Balance Sheet [Abstract]      
Accrued expenses 7.1 9.2  
Postretirement benefit liabilities 50.9 60.7  
Net amount recognized 58.0 69.9  
Prior Service Costs (Credits) [Abstract]      
Beginning balance (24.3) (23.4)  
Prior service costs (credits) arising during the period (0.2) (6.1)  
Amount recognized as component of net benefit costs 6.3 5.2  
Ending balance (18.2) (24.3) (23.4)
Net Actuarial Losses [Abstract]      
Beginning balance 15.0 13.2  
Actuarial losses (gains) arising during the period (5.5) 2.8  
Amount recognized as component of net benefit costs (0.7) (1.0)  
Ending balance 8.8 15.0 13.2
Total (9.4) (9.3)  
Estimated pretax prior service (cost) credit in accumulated other comprehensive income (loss) expected to be recognized over the next year 5.7    
Estimated pretax net actuarial loss in accumulated other comprehensive income (loss) expected to be recognized over the next year 1.3    
Defined Benefit Plan, Weighted average assumptions used to determine pension and other postretirement benefit obligations [Abstract]      
Discount rate 3.60% 4.20%  
Rate of compensation increase 0.00% [9] 0.00% [9]  
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]      
Discount rate (in hundredths) 4.20% [10]   5.45% [10]
Defined Benefit Plan, Assets, Target Allocations [Abstract]      
Fair value of plan assets 0 0 0
Expected Benefit Payments [Abstract]      
Company contributions expected to be made in 2013 7.1 [12]    
2013 7.1    
2014 6.0    
2015 5.4    
2016 4.9    
2017 4.6    
2018-2022 $ 17.6    
Other Postretirement Benefit Plans [Member] | Minimum [Member]
      
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]      
Discount rate (in hundredths)   4.65% [10]  
Other Postretirement Benefit Plans [Member] | Maximum [Member]
      
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]      
Discount rate (in hundredths)   4.80% [10]  
[1] See Note 6 – Fair Value Measurements for a description of levels within the fair value hierarchy. The level in the fair value hierarchy within which the fair value measurement is classified is determined based on the lowest level input that is significant to the fair value measurement in its entirety. A description of the valuation methodologies is provided following these tables. There were no significant transfers in and/or out of Level 1, Level 2 and Level 3 in 2011.
[2] See Note 6 – Fair Value Measurements for a description of levels within the fair value hierarchy. The level in the fair value hierarchy within which the fair value measurement is classified is determined based on the lowest level input that is significant to the fair value measurement in its entirety. A description of the valuation methodologies is provided following these tables. There were no transfers in and/or out of Level 1, Level 2 and Level 3 in 2012.
[3] The equity assets are invested in two indexed funds based on the Russell 3000 Index (U.S.) and the MSCI EAFE Equity Index (International). The Trust did not directly own any of the Company's common stock as of December 31, 2012.
[4] The majority of equity assets are invested in two indexed funds based on the Russell 3000 Index (U.S.) and the MSCI EAFE Equity Index (International). The Trust did not directly own any of the Company's common stock as of December 31, 2011.
[5] Government securities are comprised primarily of U.S. Treasury bonds and other government securities.
[6] Corporate securities consist primarily of investment grade bonds issued by companies in diversified industries.
[7] This class includes commingled funds that primarily invest in investment grade corporate securities and government-related securities. This class also includes investments in non-agency collateralized mortgage obligation and mortgage-backed securities, futures and options.
[8] This class includes interest receivable and receivables/payables for securities sold/purchased.
[9] Assumption used in determining pension benefit obligation only. The rate of compensation increase was reduced to 0.00% at December 31, 2008, as a result of the decision to freeze future benefit accruals for those plans where benefits are based on average compensation.
[10] Range of discount rates in 2011 reflects the remeasurements of pension and postretirement benefit costs during the year due to negative plan amendments and curtailments recognized.
[11] Assumption used in determining pension benefit cost only.
[12] The Company currently anticipates contributing approximately $50.0 million to fund the qualified pension plans and approximately $4.0 million to cover benefit payments in the unfunded, nonqualified pension plan in 2013. Company contributions are subject to change based on market conditions or Company discretion.