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Long-term Bank Loans - Additional Information (Detail) $ in Millions |  | 3 Months Ended
--- | --- | ---
May 15, 2018 TWD ($) Bank | Mar. 31, 2020 TWD ($)
Maximum [Member] |  |
Disclosure of detailed information about borrowings [Line Items] |  |
Maturity of loan |  | ten years
Minimum [Member] |  |
Disclosure of detailed information about borrowings [Line Items] |  |
Maturity of loan |  | seven years
Syndicated loan [member] |  |
Disclosure of detailed information about borrowings [Line Items] |  |
Number of banks in syndicate | Bank | 11 |
Principal amount of loan | $ 12,000 |
Maturity of loan | five years |
Government granted bank loans [Member] |  |
Disclosure of detailed information about borrowings [Line Items] |  |
Principal amount of loan |  | $ 12,144

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- Details
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- Details
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