XML 453 R250.htm IDEA: XBRL DOCUMENT
v3.10.0.1

Post-retirement benefits - Summary of maturity of defined benefit obligations (Detail) - yr | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Disclosure of defined benefit plans [Line Items] |  |  |
Proportion relating to current employees | 19.00% | 20.00% | 21.00%
Proportion relating to former employees not yet retired | 11.00% | 11.00% | 12.00%
Proportion relating to retirees | 70.00% | 69.00% | 67.00%
Defined benefit obligation | 100.00% | 100.00% | 100.00%
Average duration of obligations (years) | 13.4 | 13.9 | 14.3
Pension benefits [member] |  |  |
Disclosure of defined benefit plans [Line Items] |  |  |
Proportion relating to current employees | 20.00% |  |
Proportion relating to former employees not yet retired | 11.00% |  |
Proportion relating to retirees | 69.00% |  |
Defined benefit obligation | 100.00% |  |
Average duration of obligations (years) | 13.4 |  |
Other Benefits [member] |  |  |
Disclosure of defined benefit plans [Line Items] |  |  |
Proportion relating to current employees | 15.00% |  |
Proportion relating to former employees not yet retired | 2.00% |  |
Proportion relating to retirees | 83.00% |  |
Defined benefit obligation | 100.00% |  |
Average duration of obligations (years) | 12.7 |  |

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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 weighted average duration of a defined benefit obligation. [Refer: Weighted average [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2017-01-01 -Paragraph 147 -Subparagraph c -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2017-03-01&anchor=para_147_c&doctype=Standard -URIDate 2017-03-09 + Details
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- Definition Defined benefit obligation maturity percentage. + References No definition available. + Details
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- Definition Defined benefit obligations relating to current employees maturity percentage. + References No definition available. + Details
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- Definition Defined benefit obligations relating to former employees not yet retired maturity percentage. + References No definition available. + Details
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- Definition Defined benefit obligations relating to retirees maturity percentage. + References No definition available. + Details
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- Details
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- Details
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Balance Type: |
Period Type: |