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General Information - Additional Information (Detail) | 12 Months Ended
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Dec. 31, 2018 $ / shares
Siliconware Precision Industries Co., Ltd. [member] |
Disclosure Of General Information About Financial Statements [line items] |
Exchange price per share | $ 51.2

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- Definition Adjusted exchange price per share. + References No definition available. + Details
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- Definition Disclosure Of General Information About Financial Statements [line items] + References No definition available. + Details
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- Details
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Balance Type: |
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