Financial Assets and Liabilities - Summary of Consolidated Foreign Currency-denominated Monetary Financial Assets and Liabilities (Parenthetical) (Detail)		12 Months Ended
Mar. 26, 2017 PHP (₱)	Dec. 31, 2017	Dec. 31, 2016
Disclosure Of Pre Tax Exposure To Foreign Currency Exchange Risk On Financial Instruments [Line Items]
Weighted Average Foreign Exchange Rate		49.96
Foreign currency exchange risk [Member]
Disclosure Of Pre Tax Exposure To Foreign Currency Exchange Risk On Financial Instruments [Line Items]
Weighted Average Foreign Exchange Rate	52.29	49.96	49.77

The average exchange rate used by the entity. Exchange rate is the ratio of exchange for two currencies.

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

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