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v3.22.1

Financial Statements Schedule: Valuation and Qualifying Accounts (Detail) - TWD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Allowance for Impairment of property, plant and equipment [member] |  |  |
Disclosure of details of valuation and qualifying accounts [Line Items] |  |  |
January 1 | $ 182,002 | $ 193,340 | $ 317,593
Additions charged to expense or deduction of revenue | 4,843 |  | 9,938
Deduction/Write-offs/Reversal | (3,666) | (11,338) | (134,191)
December 31 | 183,179 | 182,002 | 193,340
Allowance for Impairment of Obsolescence and Decline in Market Value of Inventories [Member] |  |  |
Disclosure of details of valuation and qualifying accounts [Line Items] |  |  |
January 1 | 79,815 | 63,498 | 36,157
Additions charged to expense or deduction of revenue | 41,771 | 16,317 | 27,341
December 31 | 121,586 | 79,815 | 63,498
Provision for deficiency compensation [member] |  |  |
Disclosure of details of valuation and qualifying accounts [Line Items] |  |  |
January 1 | 3,463 | 1,998 | 29,352
Additions charged to expense or deduction of revenue | 11,898 | 4,358 | 5,204
Deduction/Write-offs/Reversal | (11,080) | (2,893) | (32,558)
December 31 | 4,281 | 3,463 | 1,998
Sales for allowance [member] |  |  |
Disclosure of details of valuation and qualifying accounts [Line Items] |  |  |
January 1 | 9,864 | 26,000 | 32,627
Additions charged to expense or deduction of revenue | 34,744 | 21,916 | 63,863
Deduction/Write-offs/Reversal | (34,759) | (38,052) | (70,490)
December 31 | $ 9,849 | $ 9,864 | $ 26,000

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- Definition Valuation allowances and reserves charged to expense. + References No definition available. + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Details
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- Details
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- Details
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- Details
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