Net Income - Other Income (Detail) $ in Millions, $ in Millions	12 Months Ended
Dec. 31, 2023 TWD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 TWD ($)	Dec. 31, 2021 TWD ($)
Analysis of income and expense [abstract]
Dividend income	$ 167	$ 5	$ 157	$ 154
Rental income	76		79	70
Others	139		133	154
Other income	$ 382	$ 12	$ 369	$ 378

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 2023-01-01
-Paragraph 112
-Subparagraph c
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2023-en-r&anchor=para_112_c&doctype=Standard
-URIDate 2023-03-23

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration