v3.26.1
Financial Instruments - Summary of Maturity Analysis for Non-derivative Financial Liabilities (Detail)
$ in Thousands, $ in Thousands
Dec. 31, 2025
TWD ($)
Dec. 31, 2025
USD ($)
Dec. 31, 2024
TWD ($)
Less than 1 month [member]      
Disclosure of maturity analysis for non-derivative financial liabilities [line items]      
Non-derivative financial liabilities undiscounted amounts $ 106,263,871 $ 3,387,436 $ 81,774,799
Less than 1 month [member] | Obligation under leases [member]      
Disclosure of maturity analysis for non-derivative financial liabilities [line items]      
Non-derivative financial liabilities undiscounted amounts 128,731 4,104 167,887
Less than 1 month [member] | Non interest bearing [member]      
Disclosure of maturity analysis for non-derivative financial liabilities [line items]      
Non-derivative financial liabilities undiscounted amounts 75,853,604 2,418,030 66,577,698
Less than 1 month [member] | Floating interest rate [member]      
Disclosure of maturity analysis for non-derivative financial liabilities [line items]      
Non-derivative financial liabilities undiscounted amounts 19,644,085 626,206 9,865,888
Less than 1 month [member] | Fixed interest rate [member]      
Disclosure of maturity analysis for non-derivative financial liabilities [line items]      
Non-derivative financial liabilities undiscounted amounts 10,637,451 339,096 5,163,326
1 to 3 months [member]      
Disclosure of maturity analysis for non-derivative financial liabilities [line items]      
Non-derivative financial liabilities undiscounted amounts 58,836,660 1,875,571 66,802,249
1 to 3 months [member] | Obligation under leases [member]      
Disclosure of maturity analysis for non-derivative financial liabilities [line items]      
Non-derivative financial liabilities undiscounted amounts 210,673 6,716 185,848
1 to 3 months [member] | Non interest bearing [member]      
Disclosure of maturity analysis for non-derivative financial liabilities [line items]      
Non-derivative financial liabilities undiscounted amounts 46,653,157 1,487,190 39,954,390
1 to 3 months [member] | Floating interest rate [member]      
Disclosure of maturity analysis for non-derivative financial liabilities [line items]      
Non-derivative financial liabilities undiscounted amounts 6,892,644 219,721 15,650,230
1 to 3 months [member] | Fixed interest rate [member]      
Disclosure of maturity analysis for non-derivative financial liabilities [line items]      
Non-derivative financial liabilities undiscounted amounts 5,080,186 161,944 11,011,781
3 months to 1 year [member]      
Disclosure of maturity analysis for non-derivative financial liabilities [line items]      
Non-derivative financial liabilities undiscounted amounts 38,641,949 1,231,812 48,783,130
3 months to 1 year [member] | Obligation under leases [member]      
Disclosure of maturity analysis for non-derivative financial liabilities [line items]      
Non-derivative financial liabilities undiscounted amounts 841,489 26,825 801,002
3 months to 1 year [member] | Non interest bearing [member]      
Disclosure of maturity analysis for non-derivative financial liabilities [line items]      
Non-derivative financial liabilities undiscounted amounts 23,722,468 756,215 18,126,780
3 months to 1 year [member] | Floating interest rate [member]      
Disclosure of maturity analysis for non-derivative financial liabilities [line items]      
Non-derivative financial liabilities undiscounted amounts 9,202,843 293,364 13,152,601
3 months to 1 year [member] | Fixed interest rate [member]      
Disclosure of maturity analysis for non-derivative financial liabilities [line items]      
Non-derivative financial liabilities undiscounted amounts 4,875,149 155,408 16,702,747
1-5 years [member]      
Disclosure of maturity analysis for non-derivative financial liabilities [line items]      
Non-derivative financial liabilities undiscounted amounts 253,157,381 8,070,047 146,133,980
1-5 years [member] | Obligation under leases [member]      
Disclosure of maturity analysis for non-derivative financial liabilities [line items]      
Non-derivative financial liabilities undiscounted amounts 3,048,712 97,186 2,676,514
1-5 years [member] | Non interest bearing [member]      
Disclosure of maturity analysis for non-derivative financial liabilities [line items]      
Non-derivative financial liabilities undiscounted amounts 34,607,140 1,103,192 4,707,506
1-5 years [member] | Floating interest rate [member]      
Disclosure of maturity analysis for non-derivative financial liabilities [line items]      
Non-derivative financial liabilities undiscounted amounts 200,799,083 6,400,991 115,539,867
1-5 years [member] | Fixed interest rate [member]      
Disclosure of maturity analysis for non-derivative financial liabilities [line items]      
Non-derivative financial liabilities undiscounted amounts 14,702,446 468,678 23,210,093
More than 5 years [member]      
Disclosure of maturity analysis for non-derivative financial liabilities [line items]      
Non-derivative financial liabilities undiscounted amounts 13,833,618 440,983 14,644,683
More than 5 years [member] | Obligation under leases [member]      
Disclosure of maturity analysis for non-derivative financial liabilities [line items]      
Non-derivative financial liabilities undiscounted amounts 7,384,494 235,400 5,572,038
More than 5 years [member] | Non interest bearing [member]      
Disclosure of maturity analysis for non-derivative financial liabilities [line items]      
Non-derivative financial liabilities undiscounted amounts 68,696 2,190 1,177,870
More than 5 years [member] | Floating interest rate [member]      
Disclosure of maturity analysis for non-derivative financial liabilities [line items]      
Non-derivative financial liabilities undiscounted amounts 6,380,428 203,393 $ 7,894,775
More than 5 years [member] | Fixed interest rate [member]      
Disclosure of maturity analysis for non-derivative financial liabilities [line items]      
Non-derivative financial liabilities undiscounted amounts $ 0 $ 0