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Summary of Significant Accounting Policies - Additional Information (Detail) - $ / $ | 1 Months Ended | 12 Months Ended
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Feb. 28, 2018 | Dec. 31, 2017
Summary Of Significant Accounting Policies [Abstract] |  |
Income tax on unappropriated earnings | 5.00% | 10.00%
Convenience exchange rate |  | 29.64

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- Definition Summary Of Significant Accounting Policies [abstract] + References No definition available. + Details
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- Definition The spot exchange rate at the end of the reporting period. Exchange rate is the ratio of exchange for two currencies. Spot exchange rate is the exchange rate for immediate delivery. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2017-01-01 -Paragraph 112 -Subparagraph c -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_112_c&doctype=Standard -URIDate 2017-03-09 + Details
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