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Summary of Significant Accounting Policies - Additional Information (Detail) | 12 Months Ended
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Dec. 31, 2017
Summary of significant accounting policies [line items] |
Business combination description | Recognized assets and liabilities may be adjusted during a maximum of 12 months from the acquisition date, depending on new information obtained about the facts and circumstances existing at the acquisition date.
Technology [member] |
Summary of significant accounting policies [line items] |
Intangible assets amortized estimated useful life | 20 years
Customer relationships [member] |
Summary of significant accounting policies [line items] |
Intangible assets amortized estimated useful life | 25 years
Bottom of range [member] | Computer software [member] |
Summary of significant accounting policies [line items] |
Intangible assets amortized estimated useful life | 3 years
Bottom of range [member] | Buildings [member] |
Summary of significant accounting policies [line items] |
Property, plant and equipment, useful life | 10 years
Bottom of range [member] | Machinery and equipment [member] |
Summary of significant accounting policies [line items] |
Property, plant and equipment, useful life | 3 years
Bottom of range [member] | Vehicles [member] |
Summary of significant accounting policies [line items] |
Property, plant and equipment, useful life | 5 years
Top of range [member] | Computer software [member] |
Summary of significant accounting policies [line items] |
Intangible assets amortized estimated useful life | 5 years
Top of range [member] | Buildings [member] |
Summary of significant accounting policies [line items] |
Property, plant and equipment, useful life | 50 years
Top of range [member] | Machinery and equipment [member] |
Summary of significant accounting policies [line items] |
Property, plant and equipment, useful life | 40 years
Top of range [member] | Vehicles [member] |
Summary of significant accounting policies [line items] |
Property, plant and equipment, useful life | 8 years

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- Definition The description of the nature and financial effect of business combinations during the current reporting period. [Refer: Business combinations [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 3 -IssueDate 2017-01-01 -Paragraph 59 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=3&date=2017-03-01&anchor=para_59_a&doctype=Standard -URIDate 2017-03-09 + Details
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