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General Information - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2019 $ / 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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