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Long-term Bank Loans - Summary of Long-term Bank Loans (Detail) $ in Thousands, $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2019 TWD ($) | Dec. 31, 2018 TWD ($) | Dec. 31, 2019 USD ($)
Disclosure of detailed information about borrowings [Line Items] |  |  |
Syndicated bank loan | $ 9,041,645 | $ 9,789,518 |
Less:Fee on syndicated bank loan | (24,355) | (32,482) |
Less: Current portion (fee included) | (748,419) | (747,422) | $ (25,023)
Syndicated bank loans, excluding current portion | 8,293,226 | 9,042,096 | $ 277,273
Long-term bank loans [Member] |  |  |
Disclosure of detailed information about borrowings [Line Items] |  |  |
Unused credit lines of long-term bank loans | $ 1,800,000 | $ 1,800,000 |
Gross carrying amount [member] |  |  |
Disclosure of detailed information about borrowings [Line Items] |  |  |
Interest rate range | 1.7895% | 1.7895% | 1.7895%
Gross carrying amount [member] | Syndicated bank loans repayable from November 2018 to May 2023 [member] |  |  |
Disclosure of detailed information about borrowings [Line Items] |  |  |
Syndicated bank loan | $ 9,066,000 | $ 9,822,000 |
Period and payment term | Borrowing period is from May 30, 2018 to May 30, 2023; interest is repayable monthly; principal is repayable semi-annually from November 30, 2018 | Borrowing period is from May 30, 2018 to May 30, 2023; interest is repayable monthly; principal is repayable semi-annually from November 30, 2018 |

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- Definition The amount of outstanding funds that the entity is obligated to repay. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2019-01-01 -Paragraph 55 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2019-en-r&anchor=para_55&doctype=Standard -URIDate 2019-03-27 + Details
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Period Type: | instant

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- Definition The interest rate on borrowings. [Refer: Borrowings] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IFRS -Number 7 -IssueDate 2019-01-01 -Paragraph 7 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2019-en-r&anchor=para_7&doctype=Standard -URIDate 2019-03-27 + Details
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- Definition The current portion of non-current borrowings. [Refer: Borrowings] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2019-01-01 -Paragraph 55 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2019-en-r&anchor=para_55&doctype=Standard -URIDate 2019-03-27 + Details
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- Definition The non-current portion of non-current borrowings. [Refer: Borrowings] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2019-01-01 -Paragraph 55 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2019-en-r&anchor=para_55&doctype=Standard -URIDate 2019-03-27 + Details
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- Definition The amount of undrawn borrowing facilities that may be available for future operating activities and to settle capital commitments. [Refer: Capital commitments] + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Name IAS -Number 7 -IssueDate 2019-01-01 -Paragraph 50 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=7&code=ifrs-tx-2019-en-r&anchor=para_50_a&doctype=Standard -URIDate 2019-03-27 + Details
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- Definition Borrowing repayable period. + References No definition available. + Details
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- Definition The amount of fee on syndicated bank loan. + References No definition available. + Details
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- Details
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- Details
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