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v3.19.1

Income Tax - Additional Information (Detail) | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Income tax [Line Items] |  |  |
Applicable tax rate | 20.00% | 17.00% | 17.00%
Unappropriated earnings [Member] |  |  |
Income tax [Line Items] |  |  |
Applicable tax rate | 5.00% | 10.00% |
China [Member] |  |  |
Income tax [Line Items] |  |  |
Applicable tax rate | 25.00% | 25.00% | 25.00%

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- Definition Income tax. + References No definition available. + Details
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- Definition The applicable income tax rate. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 12 -IssueDate 2018-01-01 -Paragraph 81 -Subparagraph c -Clause ii -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=12&date=2018-03-01&anchor=para_81_c_ii&doctype=Standard -URIDate 2018-03-16 + Details
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- Details
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- Details
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