Employee Benefits - U.S. and Canadian Other Post-Retirement Benefits Narrative (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Expected future benefit payments 2024	$ 5.0
Other Post-Retirement Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Unrecognized prior-service cost	1.0	$ 1.0
Unrecognized loss	3.0	$ (6.0)
Amounts in Accumulated other comprehensive income (loss) expected to be recognized as components of net periodic benefit cost in next fiscal year	0.8
Expected employer contributions during next fiscal year	4.0
Expected future benefit payments 2020	5.0
Expected future benefit payments 2021	5.0
Expected future benefit payments 2022	5.0
Expected future benefit payments 2023	5.0
Expected future benefit payments 2025-2029	25.0
Effect of one percentage point increase on accumulated postretirement benefit obligation	3.0
Effect of one percentage point decrease on accumulated postretirement benefit obligation	2.0
Effect of one percentage point increase on service cost and interest cost components of net periodic benefit cost	0.1
Effect of one percentage point decrease on service cost and interest cost components of net periodic benefit cost	$ 0.1
Maximum percentage of liability for future plan cost increases for pre-65 and medical supplement plan coverage	5.00%
Maximum percentage of medical supplement plan into future periods	5.00%
Other Post-Retirement Benefits \| Maximum
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Maximum percentage of liability for future plan cost increases for pre-65 and medical supplement plan coverage	7.00%
Other Post-Retirement Benefits \| Minimum
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Maximum percentage of liability for future plan cost increases for pre-65 and medical supplement plan coverage	4.00%

Defined Benefit Plan Maximum Percentage of Medical Supplement Plan Into Future Periods

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Represents the percentage of medical supplement plan coverage for defined benefit plan.

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Amount, before tax, of accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit.

+ References

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-Publisher FASB
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Amount, before tax, of accumulated other comprehensive (income) loss for cost (credit) of benefit change attributable to participants' prior service from plan amendment or plan initiation of defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

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Amount of decrease in accumulated postretirement benefit obligation from one-percentage-point decrease in assumed health care cost trend rate.

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Amount of decrease in service and interest cost components of net periodic postretirement benefit cost from one-percentage-point decrease in assumed health care cost trend rate.

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Amount of increase in accumulated postretirement benefit obligation from one-percentage-point increase in assumed health care cost trend rate.

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Amount of increase in service and interest cost components of net periodic postretirement benefit cost from one-percentage-point increase in assumed health care cost trend rate.

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Amount included in accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan expected to be recognized in net periodic benefit (cost) credit for fiscal year following most recent annual statement of financial position.

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Amount of benefits for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in next fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in fifth fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in fourth fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in third fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in second fiscal year following latest fiscal year.

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Amount of contributions expected to be received by defined benefit plan from employer in next fiscal year following latest fiscal year.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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