Defined Benefit Plan, Number of New Entrants after Pension Plans were Frozen

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- Definition

Defined Contribution Plan, Employer Matching Contribution, Maximum Annual Contribution, Percent

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- Definition

Amount of funded (unfunded) status of defined benefit plan, measured as difference between fair value of plan assets and benefit obligation. Includes, but is not limited to, overfunded (underfunded) status.

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- Definition

Amount of cost for defined contribution plan.

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- Definition

Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

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Percentage employer matches of the employee's percentage contribution matched.

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Maximum amount the employee may contribute to a defined contribution plan.

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- Definition

Amount of cost for employer contribution to multiemployer plan. Multiemployer plan includes, but is not limited to, pension plan determined to be individually significant and insignificant and other postretirement benefit plan.

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Amount, after tax, of gain (loss) for (increase) decrease in value of benefit obligation for change in actuarial assumptions and increase (decrease) in value of plan assets from experience different from that assumed of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit.

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Employee Benefit Plans (Details) $ in Millions		12 Months Ended
Employee Benefit Plans (Details) $ in Millions	Jan. 01, 2021 CAD ($)	Dec. 31, 2020 USD ($) entrant	Dec. 31, 2020 CAD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Number of new entrants since plans were frozen \| entrant		0
Multi-employer defined benefit plan contributions		$ 0.5		$ 0.5	$ 0.5
Employer matching contribution, percent of match		50.00%	50.00%
Percentage of employees' base salary for which Company contributes a matching contribution		6.00%	6.00%
Maximum annual contribution employees could elect to contribute, percent		3.00%	3.00%
Employer discretionary contribution amount		$ 3.1		6.1	$ 5.6
Canada
Defined Benefit Plan Disclosure [Line Items]
Maximum annual contributions per employee (in CAD)			$ 27,230
Canada \| Subsequent Event
Defined Benefit Plan Disclosure [Line Items]
Maximum annual contributions per employee (in CAD)	$ 27,830
Other Post-retirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Unfunded amount of liability recognized in the balance sheet		2.8		2.4
Net actuarial gain (loss) recognized in AOCI		$ 0.4		$ (0.1)