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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, 2018 | Dec. 31, 2017
Change in plan assets: |  |
Fair value of plan assets at beginning of year | $ 72.3 |
Fair value of plan assets at end of year | 68.1 | $ 72.3
Accrued Annual Veba Contribution | 2.1 | 15.7
Net liabilities of Salaried VEBA | 32.4 | 31.9
VEBAs |  |
Change in benefit obligation: |  |
Obligation at beginning of year | 90.0 | 86.8
Defined Benefit Plan, Benefit Obligation, Foreign Currency Translation Gain (Loss) | 0.0 | 0.0
Defined Benefit Plan, Service Cost | 0.0 | 0.0
Defined Benefit Plan, Interest Cost | 2.8 | 3.0
Defined Benefit Plan, Benefit Obligation, Increase (Decrease) for Plan Amendment | 6.9 | 7.3
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss) | 6.8 | 0.5
Benefits paid by VEBA | (7.3) | (6.6)
Obligation at end of year | 85.6 | 90.0
Change in plan assets: |  |
Fair value of plan assets at beginning of year | 58.1 | 58.2
Defined Benefit Plan, Plan Assets, Increase (Decrease) for Actual Return (Loss) | 0.3 | 3.6
Defined Benefit Plan, Plan Assets, Contributions by Employer | 2.1 | 2.9
Benefits paid by VEBA | (7.3) | (6.6)
Fair value of plan assets at end of year | 53.2 | 58.1
Defined Benefit Plan, Funded (Unfunded) Status of Plan | (32.4) | (31.9)
Salaried VEBA |  |
Change in plan assets: |  |
Actuarial (gain) loss due to projected lower benefit utilization | (2.2) | (1.0)
Actuarial (Gain) Loss Due To Change In Discount Rate | (5.1) | 3.0
Actuarial (Gain) Loss Due To Changes In Census Data | 0.5 | (2.5)
Accrued Annual Veba Contribution | 2.1 | 2.9
Defined Benefit Plan, Funded (Unfunded) Status of Plan | (32.4) | (31.9)
Union VEBA |  |
Change in plan assets: |  |
Accrued Annual Veba Contribution |  | 12.8
Canadian pension plan |  |
Change in plan assets: |  |
Defined Benefit Plan, Benefit Obligation, Contributions by Plan Participant | 0.1 | 0.1
Canadian pension plan | Canadian pension plan |  |
Change in benefit obligation: |  |
Obligation at beginning of year | 8.5 | 7.0
Defined Benefit Plan, Benefit Obligation, Foreign Currency Translation Gain (Loss) | (0.7) | 0.5
Defined Benefit Plan, Service Cost at Balance Sheet Exchange Rate | 0.3 | 0.3
Defined Benefit Plan, Interest Cost at Balance Sheet Exchange Rate | 0.3 | 0.3
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss) | 0.6 | (0.6)
Obligation at end of year | 7.3 | 8.5
Change in plan assets: |  |
Fair value of plan assets at beginning of year | 7.3 | 6.1
Defined Benefit Plan, Plan Assets, Foreign Currency Translation Gain (Loss) | (0.6) | 0.5
Defined Benefit Plan, Plan Assets, Increase (Decrease) for Actual Return (Loss) | (0.2) | 0.5
Defined Benefit Plan, Plan Assets, Contributions by Employer | 0.5 | 0.4
Defined Benefit Plan, Plan Assets, Benefits Paid | 0.6 | 0.3
Fair value of plan assets at end of year | 6.5 | 7.3
Defined Benefit Plan, Funded (Unfunded) Status of Plan | $ (0.8) | $ (1.2)

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