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Summary Of Significant Accounting Policies - Disclosure of Foreign Exchange Rates (Detail) | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
U.S. Dollar [member] |  |  |
Disclosure of foreign exchange rates [line items] |  |  |
Average rate | 1.1798 | 1.1273 | 1.1063
Closing rate | 1.1450 | 1.1993 | 1.0541
Swiss Franc [member] |  |  |
Disclosure of foreign exchange rates [line items] |  |  |
Average rate | 1.1546 | 1.1103 | 1.0901
Closing rate | 1.1269 | 1.1702 | 1.0739
Czech Republic, Koruny [member] |  |  |
Disclosure of foreign exchange rates [line items] |  |  |
Average rate | 25.6452 | 26.3151 | 27.0342
Closing rate | 25.7240 | 25.5349 | 27.0210

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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 2018-01-01 -Paragraph 112 -Subparagraph c -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_112_c&doctype=Standard -URIDate 2018-03-16 + 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 2018-01-01 -Paragraph 112 -Subparagraph c -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_112_c&doctype=Standard -URIDate 2018-03-16 + Details
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