Consideration paid in cash.

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- Definition

Disclosure of investments accounted for using equity method.

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No definition available.

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- Definition

Ordinary shares issued.

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No definition available.

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- Definition

The gain (loss) recognised as result of remeasuring to fair value the equity interest in the acquiree held by the acquirer before the business combination. [Refer: Business combinations [member]]

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The amount of impairment loss on financial assets. [Refer: Financial assets; Impairment loss]

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The amount of investments in joint ventures in an entity's separate financial statements. [Refer: Joint ventures [member]]

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The nominal value per share.

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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) $ / shares in Units, ¥ in Thousands, shares in Thousands, $ in Thousands, $ in Thousands				1 Months Ended		12 Months Ended
	Jun. 30, 2020 TWD ($) $ / shares shares	Jun. 30, 2020 USD ($)	Mar. 31, 2019	Apr. 30, 2019 TWD ($)	Mar. 31, 2019 CNY (¥)	Dec. 31, 2020 TWD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 TWD ($)	Dec. 31, 2018 TWD ($)	Dec. 31, 2021 TWD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Disclosure of Investments Accounted for Using Equity Method [line Items]
Gain on disposal of investments accounted for using the equity method				$ 243,057
Impairment losses on financial assets								$ 400,201	$ 521,010
Investments in joint ventures						$ 471,434		279,702				$ 16,789
Deca Technologies Inc [member]
Disclosure of Investments Accounted for Using Equity Method [line Items]
Gain on disposal of investments accounted for using the equity method						$ 17,180	$ 612
Impairment losses on financial assets								$ 400,201
Percentage of Ownership (%)						17.85%	17.85%
ChipMos Technologies Inc [member]
Disclosure of Investments Accounted for Using Equity Method [line Items]
Gain on disposal of investments accounted for using the equity method	$ 74,117	$ 2,639
Disposal of Ordinary shares \| shares	70,000
Percentage of Ownership (%)						10.85%	10.85%
Nominal value per share \| $ / shares	$ 32
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%
Investments in joint ventures										$ 469,307	$ 16,713
SUMA-USI Electronics Co., Ltd. [member] \| Cancon Information Industry Co Ltd [Member]
Disclosure of Investments Accounted for Using Equity Method [line Items]
Consideration paid in cash for shares \| ¥					¥ 107,800