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Hedging Derivative Financial Instruments - Outstanding Forward Exchange Contracts (Detail) - 12 months ended Dec. 31, 2017 - Forward exchange contracts [Member] - Cash flow hedges [member] € in Millions, $ in Millions | TWD ($) | EUR (€)
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Disclosure Of Detailed Information About Hedging Instruments [Line Items] |  |
Currency | EUR/NT$ |
Maturity Period | 2018.03-06 |
Contract Amount | $ 142 | € 4

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- Definition Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table. + References No definition available. + Details
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- Definition Aggregate notional amount specified by the derivative(s). Expressed as an absolute value. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Article 12 -Section 13 -Sentence Column B + Details
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- Details
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