Disclosure of investments accounted for using equity method.

No definition available.

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- Definition

The amount of investments accounted for using the equity method. The equity method is a method of accounting whereby the investment is initially recognised at cost and adjusted thereafter for the post-acquisition change in the investor's share of net assets of the investee. The investor's profit or loss includes its share of the profit or loss of the investee. The investor's other comprehensive income includes its share of the other comprehensive income of the investee. [Refer: At cost [member]]

+ References

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- Definition

The proportion of ownership interest in an associate attributable to the entity. [Refer: Associates [member]]

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The proportion of ownership interest in a joint venture attributable to the entity. [Refer: Joint ventures [member]]

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The proportion of ownership interest in a subsidiary attributable to the entity. [Refer: Subsidiaries [member]]

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Investments Accounted for Using the Equity Method - Additional Information (Detail) $ in Thousands, $ in Thousands				12 Months Ended
	Jun. 30, 2021	Mar. 31, 2021 USD ($)	Mar. 31, 2019	Dec. 31, 2021 TWD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 TWD ($)	Dec. 31, 2019 TWD ($)
Disclosure of Investments Accounted for Using Equity Method [line Items]
Investments accounted for using equity method				$ 16,996,600	$ 612,711	$ 12,806,673	$ 12,085,207
CHIPLETZ [Member]
Disclosure of Investments Accounted for Using Equity Method [line Items]
Proportion of ownership interest in associate				20.82%
ISE Labs, Inc [Member] \| CHIPLETZ [Member]
Disclosure of Investments Accounted for Using Equity Method [line Items]
Proportion of ownership interest in associate		20.82%
Investments accounted for using equity method		$ 8,000
SUMA-USI Electronics Co., Ltd. [member]
Disclosure of Investments Accounted for Using Equity Method [line Items]
Percentage of ownership interest in joint venture			49.00%
YANN YUAN INVESTMENT CO., LTD [member]
Disclosure of Investments Accounted for Using Equity Method [line Items]
Percentage of Ownership (%)	29.45%