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Basis of Presentation of Financial Statements and Principal Accounting Policies - Additional Information (Detail) $ in Thousands, $ in Thousands | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2019 TWD ($) | Dec. 31, 2019 USD ($) | Jan. 01, 2019 TWD ($)
Disclosure of detailed information about basis of presentation of financial statements and principal accounting policies [line items] |  |  |
Right-of-use asset | $ 687,068 | $ 22,971 |
Lease liability | 692,951 |  |
Rent Expense | $ 28,126 |  |
Bottom of range [member] |  |  |
Disclosure of detailed information about basis of presentation of financial statements and principal accounting policies [line items] |  |  |
Incremental borrowing interest rate |  |  | 1.7895%
Top of range [member] |  |  |
Disclosure of detailed information about basis of presentation of financial statements and principal accounting policies [line items] |  |  |
Incremental borrowing interest rate |  |  | 3.9474%
Effects of adopting new standards [member] |  |  |
Disclosure of detailed information about basis of presentation of financial statements and principal accounting policies [line items] |  |  |
Right-of-use asset |  |  | $ 898,387
Lease liability |  |  | 884,275
Lease assets |  |  | 31,904
Lease obligations payable |  |  | $ 17,792

X
- Definition The amount of liabilities related to the entity's leases. Lease is a contract, or part of a contract, that conveys the right to use an underlying asset for a period of time in exchange for consideration. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 16 -IssueDate 2019-01-01 -Paragraph 47 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2019-en-r&anchor=para_47_b&doctype=Standard -URIDate 2019-03-27 + Details
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Period Type: | instant

X
- Definition The amount of assets that represent a lessee's right to use an underlying asset for the lease term. Underlying asset is an asset that is the subject of a lease, for which the right to use that asset has been provided by a lessor to a lessee. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 16 -IssueDate 2019-01-01 -Paragraph 53 -Subparagraph j -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2019-en-r&anchor=para_53_j&doctype=Standard -URIDate 2019-03-27 + Details
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X
- Definition The weighted average lessee's incremental borrowing rate applied to lease liabilities recognised in the statement of financial position at the date of initial application of IFRS 16. The incremental borrowing rate is the rate of interest that a lessee would have to pay to borrow over a similar term, and with a similar security, the funds necessary to obtain an asset of a similar value to the right-of-use asset in a similar economic environment. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 16 -IssueDate 2019-01-01 -Paragraph C12 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2019-en-r&anchor=para_C12_a&doctype=Appendix&subtype=C -URIDate 2019-03-27 + Details
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X
- Definition Line items representing detailed information about basis of presentation of financial statements and principal accounting policies. + References No definition available. + Details
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- Definition Long-term lease obligations payable. + References No definition available. + Details
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- Definition Operating lease rental expense. + References No definition available. + Details
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Period Type: | duration

X
- Definition The amount of assets recognized by the entity, which are leased under finance leases. + References No definition available. + Details
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- Details
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- Details
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- Details
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