v3.26.1
Investments Accounted for Using the Equity Method - Summary of Investments in Associates Accounted for Using the Equity Method (Detail)
$ in Thousands, $ in Thousands
 1 Months Ended 12 Months Ended
Aug. 31, 2025
Dec. 31, 2025
TWD ($)
Dec. 31, 2024
TWD ($)
Dec. 31, 2025
USD ($)
Disclosure of associates and joint ventures [line items]        
Investments in associates   $ 25,030,827 $ 20,410,983 $ 797,922
Yann Yuan Investment Co., Ltd. [member]        
Disclosure of associates and joint ventures [line items]        
Main Business   Engaged in investing activities    
Operating Location   R.O.C.    
Investments in associates before deferred gain on transfer of land   $ 13,972,765 $ 10,317,044 445,418
Percentages of ownership held by the Group   27.94% 27.94%  
Hung Ching Development & Construction Co. [member]        
Disclosure of associates and joint ventures [line items]        
Main Business   Engaged in the development, construction and leasing of real estate properties    
Operating Location   R.O.C.    
Investments in associates before deferred gain on transfer of land   $ 3,375,196 $ 2,412,818 107,593
Percentages of ownership held by the Group   26.22% 26.22%  
ChipMOS Technologies Inc. [member]        
Disclosure of associates and joint ventures [line items]        
Main Business   Engaged in the packaging and testing of semiconductors    
Operating Location   R.O.C.    
Investments in associates before deferred gain on transfer of land   $ 2,929,073 $ 2,941,982 93,372
Percentages of ownership held by the Group   11.27% 10.85%  
M-Universe Investments Pte. Ltd. [member]        
Disclosure of associates and joint ventures [line items]        
Main Business   Investment company    
Operating Location   Singapore    
Investments in associates before deferred gain on transfer of land   $ 2,362,319 $ 2,325,475 75,305
Percentages of ownership held by the Group   42.23% 42.23%  
MACHVISION Inc [Member]        
Disclosure of associates and joint ventures [line items]        
Main Business   Engaged in the manufacturing and trading of non-contact optical inspection equipment    
Operating Location   R.O.C.    
Investments in associates before deferred gain on transfer of land   $ 2,120,140 $ 2,055,590 67,585
Percentages of ownership held by the Group   23.08% 23.08%  
CHIPLETZ [Member]        
Disclosure of associates and joint ventures [line items]        
Main Business   Fabless substrate design house    
Operating Location   U.S.A.    
Percentages of ownership held by the Group   18.74% 18.74%  
Deca Technologies Inc. [member]        
Disclosure of associates and joint ventures [line items]        
Main Business   Holding company with group engaged in the development of packaging of semiconductors    
Operating Location   U.S.A.    
Percentages of ownership held by the Group   17.82% 17.84%  
QUESTYLE [member]        
Disclosure of associates and joint ventures [line items]        
Main Business   Engaged in the research and development on technology and sales of electronic products, digital products, audio equipment and spare parts, domestic trading, import and export business    
Operating Location   China    
Percentages of ownership held by the Group   0.00% 6.67%  
Goodcare Holdings Inc [Member]        
Disclosure of associates and joint ventures [line items]        
Main Business   Holding company, engaged in business of investment, long-term care and home care services    
Operating Location   R.O.C.    
Percentages of ownership held by the Group 67.21% 0.00% 49.00%  
Hung Ching Kwan Co. [member]        
Disclosure of associates and joint ventures [line items]        
Main Business   Engaged in the leasing of real estate properties    
Operating Location   R.O.C.    
Percentages of ownership held by the Group   27.31% 27.31%  
Cost [member]        
Disclosure of associates and joint ventures [line items]        
Investments in associates   $ 24,931,517 $ 20,327,885 794,757
Cost [member] | CHIPLETZ [Member]        
Disclosure of associates and joint ventures [line items]        
Investments in associates before deferred gain on transfer of land   192,314 255,384 6,130
Cost [member] | Deca Technologies Inc. [member]        
Disclosure of associates and joint ventures [line items]        
Investments in associates before deferred gain on transfer of land   79,020 58,100 2,519
Cost [member] | QUESTYLE [member]        
Disclosure of associates and joint ventures [line items]        
Investments in associates before deferred gain on transfer of land   0 17,798 0
Cost [member] | Goodcare Holdings Inc [Member]        
Disclosure of associates and joint ventures [line items]        
Investments in associates before deferred gain on transfer of land   0 26,792 0
Cost [member] | Hung Ching Kwan Co. [member]        
Disclosure of associates and joint ventures [line items]        
Investments in associates before deferred gain on transfer of land   (99,310) (83,098) (3,165)
Deferred gain on transfer of land [member]        
Disclosure of associates and joint ventures [line items]        
Investments in associates   $ 99,310 $ 83,098 $ 3,165