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Benefit Plans and Other Postretirement Benefits (Tables)
9 Months Ended
Sep. 30, 2023
Benefit Plans and Other Postretirement Benefits  
Schedule of components of net pension expense

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Three Months Ended September 30, 

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Nine Months Ended September 30, 

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2023

 

2022

  

2023

 

2022

Service cost

 

$

1.8

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$

1.5

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$

5.5

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$

4.5

Interest cost

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6.5

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3.4

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19.5

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10.5

Expected return on plan assets

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(7.3)

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(7.5)

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(21.8)

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(22.5)

Amortization of prior service cost

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0.4

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0.4

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1.3

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1.1

Amortization of net actuarial losses

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0.6

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4.0

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1.6

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12.2

Net pension expense

 

$

2.0

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$

1.8

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$

6.1

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$

5.8