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Investment Properties - Investment Properties Depreciated Using Straight-Line Method Over Their Estimated Useful Lives (Detail) | 12 Months Ended
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Dec. 31, 2017
Bottom of range [member] | Main plant buildings [Member] |
Disclosure of detailed information about investment property [line items] |
Investment properties are depreciated using the straight-line method over their estimated useful lives | 10 years
Bottom of range [member] | Other Investment Properties [Member] |
Disclosure of detailed information about investment property [line items] |
Investment properties are depreciated using the straight-line method over their estimated useful lives | 3 years
Top of range [member] | Main plant buildings [Member] |
Disclosure of detailed information about investment property [line items] |
Investment properties are depreciated using the straight-line method over their estimated useful lives | 40 years
Top of range [member] | Other Investment Properties [Member] |
Disclosure of detailed information about investment property [line items] |
Investment properties are depreciated using the straight-line method over their estimated useful lives | 20 years

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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 useful lives or depreciation rates used for investment property. [Refer: Investment property] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 40 -IssueDate 2017-01-01 -Paragraph 79 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=40&date=2017-03-01&anchor=para_79_b&doctype=Standard -URIDate 2017-03-09 + Details
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- Details
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- Details
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- Details
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- Details
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