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Pension and Non-pension Post-employment Benefit Plans - Surplus (Deficit) in Defined Benefit Pension and Other Benefit Plans (Details) - USD ($) $ in Millions | Dec. 31, 2018 | Dec. 31, 2017
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Disclosure of net defined benefit liability (asset) [line items] |  |
Plan assets, end of year | $ 293.0 | $ 395.5
Pension Plans |  |
Disclosure of net defined benefit liability (asset) [line items] |  |
Accrued benefit obligations, end of year | (309.6) | (355.8)
Plan assets, end of year | 293.0 | 395.5
Excess (deficiency) of plan assets over accrued benefit obligations | (16.6) | 39.7
Other Benefit Plans |  |
Disclosure of net defined benefit liability (asset) [line items] |  |
Accrued benefit obligations, end of year | (68.1) | (75.5)
Plan assets, end of year | 0.0 | 0.0
Excess (deficiency) of plan assets over accrued benefit obligations | $ (68.1) | $ (75.5)

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- Definition The present value, without deducting any plan assets, of expected future payments required to settle the obligation resulting from employee service in the current and prior periods. [Refer: Plan assets, at fair value] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 19 -IssueDate 2017-01-01 -Paragraph 57 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2017-03-01&anchor=para_57_a&doctype=Standard -URIDate 2017-03-09 + Details
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Period Type: | instant

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- Definition Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table. + References No definition available. + Details
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- Definition The fair value of defined benefit plan assets. Plan assets comprise assets held by a long-term employee benefit fund and qualifying insurance policies. [Refer: At fair value [member]] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 19 -IssueDate 2017-01-01 -Paragraph 57 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2017-03-01&anchor=para_57_a&doctype=Standard -URIDate 2017-03-09 + Details
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Balance Type: | debit
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- Definition The present value of the defined benefit obligation, less the fair value of the plan assets (if any). [Refer: Plan assets [member]] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 19 -IssueDate 2017-01-01 -Paragraph 57 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2017-03-01&anchor=para_57_a&doctype=Standard -URIDate 2017-03-09 + Details
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- Details
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- Details
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Namespace Prefix: |
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