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

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- Definition

Amount of contribution received by defined benefit plan from employer which increases plan assets.

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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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- 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 gain (loss) recognized in net periodic benefit (cost) credit from irrevocable action relieving primary responsibility for benefit obligation and eliminating risk related to obligation and assets used to effect settlement.

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- Definition

Amount of payment, which decreases plan assets of defined benefit plan, for irrevocable action relieving primary responsibility for benefit obligation and eliminating risk for obligation and assets used to effect settlement. Transaction constituting settlement includes, but is not limited to, making lump-sum cash payment to participant in exchange for their rights to receive specified benefits and purchasing nonparticipating annuity contract.

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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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- Definition

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

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- Definition

Amount of contributions made to multiemployer plan by employer.

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Employee Benefit Plans (Details) $ in Millions		1 Months Ended	12 Months Ended
Employee Benefit Plans (Details) $ in Millions	Jan. 01, 2020 CAD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2019 USD ($) entrant	Dec. 31, 2019 CAD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Number of new entrants since plans were frozen \| entrant			0
Unrecognized actuarial losses in AOCI		$ 17.2	$ 0.0		$ 0.0	$ 17.2
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			$ 6.1		5.6	4.8
Canada
Defined Benefit Plan Disclosure [Line Items]
Maximum annual contributions per employee (in CAD)				$ 26,500
Canada \| Subsequent Event
Defined Benefit Plan Disclosure [Line Items]
Maximum annual contributions per employee (in CAD)	$ 27,230
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Employer contributions						$ 4.9
Plan termination - annuity transfer		$ (29.2)
Other Post-retirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Unfunded amount of liability recognized in the balance sheet			2.4		2.2
Net actuarial gain recognized in AOCI			$ 0.1		$ 0.4