Net Income - Other Income (Detail) $ in Millions, $ in Millions	12 Months Ended
Dec. 31, 2022 TWD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 TWD ($)	Dec. 31, 2020 TWD ($)
Analysis of income and expense [abstract]
Dividend income	$ 157	$ 5	$ 154	$ 246
Rental income	79		70	70
Others	133		154	154
Other income	$ 369	$ 13	$ 378	$ 470

The amount of dividends recognised as income. Dividends are distributions of profits to holders of equity investments in proportion to their holdings of a particular class of capital.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2022-03-24
-Paragraph 112
-Subparagraph c
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2022-en-r&anchor=para_112_c&doctype=Standard
-URIDate 2022-03-24

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