Subsidiaries - Summary of Impact of Acquisition on Financial Results of Company (Detail) - IISI and its Subsidiaries [Member] $ in Millions	6 Months Ended
Dec. 31, 2020 TWD ($)
Disclosure Of Business Combinations [Line Items]
Revenue	$ 1,348
Profit	$ 68

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table.

No definition available.

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- Definition

The profit (loss) of the acquiree, since the acquisition date, included in the consolidated statement of comprehensive income. [Refer: Profit (loss)]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 3
-IssueDate 2022-03-24
-Paragraph B64
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-Clause i
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The amount of revenue of the acquiree since the acquisition date included in the consolidated statement of comprehensive income. [Refer: Revenue]

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