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Assets Pledged as Collateral - Summary of Assets Pledged as Collateral (Detail) - TWD ($) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2024 | Dec. 31, 2023
Assets Pledged As Collateral [Line Items] |  |
Assets pledged as collateral | $ 10,570,318 | $ 14,027,423
Refundable deposits time deposit [member] | Customs [member] |  |
Assets Pledged As Collateral [Line Items] |  |
Assets pledged as collateral | $ 1,009,000 | 813,289
Purpose of pledge | Customs duty guarantee |
Refundable deposits time deposit [member] | Science Park Bureau [member] |  |
Assets Pledged As Collateral [Line Items] |  |
Assets pledged as collateral | $ 237,051 | 236,556
Purpose of pledge | Collateral for land lease |
Refundable deposits time deposit [member] | Science Park Bureau [member] | Dormitory Lease [member] |  |
Assets Pledged As Collateral [Line Items] |  |
Assets pledged as collateral | $ 18,647 | 18,647
Purpose of pledge | Collateral for dormitory lease |
Refundable deposits time deposit [member] | National Property Administration, Ministry of Finance [member] |  |
Assets Pledged As Collateral [Line Items] |  |
Assets pledged as collateral | $ 64,950 | 64,950
Purpose of pledge | Guarantee for the application of national non-public use land for development |
Refundable deposits time deposit [member] | Bureau of Land Administration, Tainan City Government [Member] |  |
Assets Pledged As Collateral [Line Items] |  |
Assets pledged as collateral | $ 8,118 | 8,118
Purpose of pledge | Guarantee for the application of national non-public use land for development |
Refundable deposits time deposit [member] | Liquefied Natural Gas Business Division, CPC Corporation, Taiwan [member] |  |
Assets Pledged As Collateral [Line Items] |  |
Assets pledged as collateral | $ 38,073 | 36,970
Purpose of pledge | Energy resources guarantee |
Refundable deposits time deposit [member] | Bank of China and Agricultural Bank of China [member] |  |
Assets Pledged As Collateral [Line Items] |  |
Assets pledged as collateral | $ 0 | 1,006,852
Purpose of pledge | Bank performance guarantee |
Refundable deposits time deposit [member] | CTBC Bank Singapore Branch [member] |  |
Assets Pledged As Collateral [Line Items] |  |
Assets pledged as collateral | $ 490,950 | 459,900
Purpose of pledge | Collateral for letter of credit |
Buildings [member] | Taiwan Cooperative Bank and Secured Syndicated Loans from China Development Bank and 6 others [member] |  |
Assets Pledged As Collateral [Line Items] |  |
Assets pledged as collateral | $ 4,377,176 | 4,487,730
Purpose of pledge | Collateral for long-term loans |
Machinery and equipment [member] | Taiwan Cooperative Bank, Mega International Commercial Bank, KGI Bank, First Commercial Bank, Shanghai Commercial Bank, CTBC Bank and Secured Syndicated Loans from China Development Bank and 6 others [member] |  |
Assets Pledged As Collateral [Line Items] |  |
Assets pledged as collateral | $ 4,057,201 | 6,627,761
Purpose of pledge | Collateral for long-term loans |
Right-of-use assets [member] | Secured Syndicated Loans from China Development Bank and 6 others [member] |  |
Assets Pledged As Collateral [Line Items] |  |
Assets pledged as collateral | $ 269,152 | $ 266,650
Purpose of pledge | Collateral for long-term loans |

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- Definition The fair value of collateral held that is permitted to be sold or repledged in the absence of default by the owner of the collateral. [Refer: At fair value [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2024-01-01 -Paragraph 15 -Subparagraph a -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2024-en-r&anchor=para_15_a&doctype=Standard -URIDate 2024-03-27 + Details
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