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Summary Of Significant Accounting Policies - Disclosure of Foreign Exchange Rates (Detail) | 6 Months Ended |
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Jun. 30, 2018 | Jun. 30, 2017 | Dec. 31, 2017
U.S. Dollar [member] |  |  |
Disclosure of foreign exchange rates [line items] |  |  |
Average rate | 1.2097 | 1.0824 |
Closing rate | 1.1658 |  | 1.1993
Swiss Franc [member] |  |  |
Disclosure of foreign exchange rates [line items] |  |  |
Average rate | 1.1696 | 1.0765 |
Closing rate | 1.1569 |  | 1.1702
Czech Republic, Koruny [member] |  |  |
Disclosure of foreign exchange rates [line items] |  |  |
Average rate | 25.4992 | 26.7809 |
Closing rate | 26.0200 |  | 25.5349

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- Definition Disclosure of foreign exchange rates. + References No definition available. + Details
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- Definition The average exchange rate used by the entity. Exchange rate is the ratio of exchange for two currencies. + 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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- 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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