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Employee Benefits, Benefit obligations and funded status of our Canadian pension and the VEBAs (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Change in plan assets: |  |  |
Fair value of plan assets at beginning of year | $ 68.1 |  |
Fair value of plan assets at end of year | 70.6 | $ 68.1 |
Accrued Annual VEBA Contribution | 2.9 | 2.1 |
Net liabilities of Salaried VEBA | 32.6 | 32.4 |
VEBAs |  |  |
Change in benefit obligation: |  |  |
Obligation at beginning of year | 85.6 | 90.0 |
Foreign currency translation adjustment | 0.0 | 0.0 |
Defined Benefit Plan, Service Cost | 0.1 | 0.1 | $ 0.0
Defined Benefit Plan, Interest Cost | 3.2 | 2.7 | 3.0
Prior service cost | 2.5 | 6.9 |
Actuarial loss (gain) | 6.4 | (6.8) |
Benefits paid by Salaried VEBA | (7.6) | (7.3) |
Obligation at end of year | 90.2 | 85.6 | 90.0
Change in plan assets: |  |  |
Fair value of plan assets at beginning of year | 53.2 | 58.1 |
Actual return on assets | 9.1 | 0.3 |
Company contributions | 2.9 | 2.1 |
Benefits paid by Salaried VEBA | (7.6) | (7.3) |
Fair value of plan assets at end of year | 57.6 | 53.2 | 58.1
Net Funded Status | (32.6) | (32.4) |
Salaried VEBA |  |  |
Change in plan assets: |  |  |
Actuarial (gain) loss due to projected lower benefit utilization | (0.5) | (2.2) |
Actuarial (gain) loss due to change in discount rate | 6.8 | (5.1) |
Actuarial (gain) loss due to changes in census data | 0.1 | 0.5 |
Accrued Annual VEBA Contribution | 2.9 | 2.1 |
Union VEBA |  |  |
Change in plan assets: |  |  |
Accrued Annual VEBA Contribution |  | 12.8 |
Canadian pension plan | Canadian pension plan |  |  |
Change in benefit obligation: |  |  |
Obligation at beginning of year | 7.3 | 8.5 |
Foreign currency translation adjustment | 0.3 | (0.7) |
Defined Benefit Plan, Service Cost | 0.3 | 0.3 | 0.3
Defined Benefit Plan, Interest Cost | 0.3 | 0.3 | 0.3
Actuarial loss (gain) | 1.1 | (0.6) |
Plan participant contributions | 0.0 | (0.1) |
Benefits paid by Company | (0.5) | (0.6) |
Obligation at end of year | 8.8 | 7.3 | 8.5
Change in plan assets: |  |  |
Fair value of plan assets at beginning of year | 6.5 | 7.3 |
Foreign currency translation adjustment | 0.3 | (0.6) |
Actual return on assets | 1.0 | (0.2) |
Plan participant contributions | 0.0 | 0.1 |
Company contributions | 0.5 | 0.5 |
Benefits paid by Company | (0.5) | (0.6) |
Fair value of plan assets at end of year | 7.8 | 6.5 | $ 7.3
Net Funded Status | $ (1.0) | $ (0.8) |

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