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Pension and Non-pension Post-employment Benefit Plans - Schedule of Non-pension Post-employment benefit plans (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Disclosure of defined benefit plans [line items] |  |  |
Plan contributions | $ 15.7 | $ 13.8 | $ 13.3
Estimated contribution | 15.4 |  |
Defined Contribution Plan |  |  |
Disclosure of defined benefit plans [line items] |  |  |
Plan contributions | 10.6 | 10.1 | 9.6
Estimated contribution | 10.6 |  |
Other benefit plans |  |  |
Disclosure of defined benefit plans [line items] |  |  |
Plan contributions | 7.8 | 9.1 | 4.8
Estimated contribution | 4.1 |  |
Pension Plan |  |  |
Disclosure of defined benefit plans [line items] |  |  |
Plan contributions | 5.1 | $ 3.7 | $ 3.7
Estimated contribution | $ 4.8 |  |

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- Definition The amount of employer contributions to retirement benefit plans. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 26 -IssueDate 2020-01-01 -Paragraph 35 -Subparagraph b -Clause i -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=26&code=ifrs-tx-2020-en-r&anchor=para_35_b_i&doctype=Standard -URIDate 2020-01-01 + Details
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- Definition The estimate of the expected contributions to be made to a defined benefit plan for the next annual reporting period. [Refer: Defined benefit plans [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2020-01-01 -Paragraph 147 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2020-en-r&anchor=para_147_b&doctype=Standard -URIDate 2020-01-01 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2020-01-01 -Paragraph 148 -Subparagraph d -Clause iii -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2020-en-r&anchor=para_148_d_iii&doctype=Standard -URIDate 2020-01-01 + Details
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