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Long Term Loans - Additional Information (Detail) - Light Era Development Co., Ltd. ("LED") [Member] - Chang Hwa Bank Secured Loan [Member] - TWD ($) $ in Millions | 1 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Apr. 30, 2015 | Dec. 31, 2020 | Dec. 31, 2017 | Sep. 30, 2010
Disclosure of detailed information about borrowings [Line Items] |  |  |  |
Early repayment of secured loan | $ 50 |  |  |
Extended Due September 2021 [Member] |  |  |  |
Disclosure of detailed information about borrowings [Line Items] |  |  |  |
Loan due date |  |  | September 2021 |
Due December 2014 [Member] |  |  |  |
Disclosure of detailed information about borrowings [Line Items] |  |  |  |
Secured loan |  |  |  | $ 300
Loan due date |  | December 2014 |  |
Due September 2015 [Member] |  |  |  |
Disclosure of detailed information about borrowings [Line Items] |  |  |  |
Secured loan |  |  |  | $ 1,350
Loan due date |  | September 2015 |  |

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- Definition The maturity of borrowings. [Refer: Borrowings] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IFRS -Number 7 -IssueDate 2020-01-01 -Paragraph 7 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2020-en-r&anchor=para_7&doctype=Standard -URIDate 2020-01-01 + Details
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- Definition The amount of loans received from banks that have been secured by collateral. [Refer: Loans received] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2020-01-01 -Paragraph 112 -Subparagraph c -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2020-en-r&anchor=para_112_c&doctype=Standard -URIDate 2020-01-01 + Details
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- Details
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- Details
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- Details
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