Financial Assets at Fair Value Through Profit or Loss - Summary of Amounts recognized in Profit or Loss in Relation to Financial Assets at Fair Value Through Profit or Loss (Detail)
$ in Thousands, $ in Thousands

12 Months Ended

Dec. 31, 2021

TWD ($)

Dec. 31, 2021

USD ($)

Dec. 31, 2020

TWD ($)

Dec. 31, 2019

TWD ($)

Financial Assets At Fair Value Through Profit Or Loss [line items]

Financial assets mandatorily measured at fair value through profit or loss

$ 15,262

$ 550

$ 24,015

$ 1,317

Foreign partnership interests [member]

Financial Assets At Fair Value Through Profit Or Loss [line items]

Financial assets mandatorily measured at fair value through profit or loss

(941)

(670)

(433)

Beneficiary certificates [member]

Financial Assets At Fair Value Through Profit Or Loss [line items]

Financial assets mandatorily measured at fair value through profit or loss

2,530

18,077

1,750

Listed stocks [member]

Financial Assets At Fair Value Through Profit Or Loss [line items]

Financial assets mandatorily measured at fair value through profit or loss

$ 13,673

$ 6,608

$ 0

Financial Assets at Fair Value Through Profit or Loss - Summary of Amounts recognized in Profit or Loss in Relation to Financial Assets at Fair Value Through Profit or Loss (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021 TWD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 TWD ($)	Dec. 31, 2019 TWD ($)
Financial Assets At Fair Value Through Profit Or Loss [line items]
Financial assets mandatorily measured at fair value through profit or loss	$ 15,262	$ 550	$ 24,015	$ 1,317
Foreign partnership interests [member]
Financial Assets At Fair Value Through Profit Or Loss [line items]
Financial assets mandatorily measured at fair value through profit or loss	(941)		(670)	(433)
Beneficiary certificates [member]
Financial Assets At Fair Value Through Profit Or Loss [line items]
Financial assets mandatorily measured at fair value through profit or loss	2,530		18,077	1,750
Listed stocks [member]
Financial Assets At Fair Value Through Profit Or Loss [line items]
Financial assets mandatorily measured at fair value through profit or loss	$ 13,673		$ 6,608	$ 0