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Pensions and Other Post-employment Benefit Obligations - Summary of Actuarial Assumptions (Parenthetical) (Detail) | Dec. 31, 2018
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2019 [member] | Pre 65 [member] |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |
Medical trend rate | 6.70%
2019 [member] | Post 65 [member] |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |
Medical trend rate | 5.80%
2026 [member] | Pre 65 [member] |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |
Medical trend rate | 4.50%
2026 [member] | Post 65 [member] |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |
Medical trend rate | 4.50%

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- Definition Medical cost trend rate used as significant actuarial assumption to determine the present value of a defined benefit obligation. [Refer: Defined benefit obligation, at present value; Actuarial assumptions [member]] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 19 -IssueDate 2018-01-01 -Paragraph 144 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2018-03-01&anchor=para_144&doctype=Standard -URIDate 2018-03-16 + Details
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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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