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Non-Cash Transactions - Non-cash Investing Activities (Detail) - TWD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Noncash Investing Activities [Abstract] |  |  |
Increase in property, plant and equipment | $ 26,069 | $ 24,591 | $ 24,451
Other payables | 806 | (1,074) | 633
Non-cash investing activities | $ 26,875 | $ 23,517 | $ 25,084

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- Definition Non-cash investing activities. + References No definition available. + Details
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- Definition Non-cash investing activities. + References No definition available. + Details
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- Definition Non-cash transactions other payables. + References No definition available. + Details
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- Definition The amount of additions to property, plant and equipment other than those acquired through business combinations. [Refer: Business combinations [member]; Property, plant and equipment] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 16 -IssueDate 2016-01-13 -Paragraph 73 -Subparagraph e -Clause i -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=16&date=2016-03-30&anchor=para_73_e_i&doctype=Standard -URIDate 2016-03-31 + Details
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