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Benefit Plans and Other Postretirement Benefits (Tables)
3 Months Ended
Mar. 31, 2022
Benefit Plans and Other Postretirement Benefits  
Schedule of components of net pension expense

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Pension Benefits

Three Months Ended March 31:

    

2022

    

2021

Service cost

 

$

1.5

 

$

1.9

Interest cost

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3.5

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2.8

Expected return on plan assets

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(7.5)

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(7.8)

Amortization of prior service cost

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0.4

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0.5

Amortization of net actuarial losses

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4.1

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6.2

Net pension expense

 

$

2.0

 

$

3.6