Earnings Per Share - Summary of Earnings and Weighted Average Number of Ordinary Shares Outstanding in Computation of Earnings Per Share (Detail) shares in Thousands, $ in Thousands, $ in Thousands |
12 Months Ended | |||
|---|---|---|---|---|
|
Dec. 31, 2025
TWD ($)
shares
|
Dec. 31, 2025
USD ($)
shares
|
Dec. 31, 2024
TWD ($)
shares
|
Dec. 31, 2023
TWD ($)
shares
|
|
| Earnings per share [line items] | ||||
| Profit for the year attributable to owners of the Company | $ 40,015,755 | $ 1,275,606 | $ 32,378,936 | $ 35,457,908 |
| Effect of potentially dilutive ordinary shares: | ||||
| Potential ordinary shares of the subsidiary | (1,268,608) | (40,440) | (747,333) | (494,272) |
| Earnings used in the computation of diluted earnings per share | $ 38,747,147 | $ 1,235,166 | $ 31,631,603 | $ 34,963,636 |
| Weighted average number of ordinary shares in the computation of basic earnings per share | 4,341,193 | 4,341,193 | 4,318,991 | 4,295,871 |
| Effect of potentially dilutive ordinary shares: | ||||
| Employee share options | 76,886 | 76,886 | 70,534 | 42,045 |
| Employees' compensation | 536 | 536 | 623 | 924 |
| Employee restricted stock awards | 10,938 | 10,938 | 1,865 | 8,830 |
| Weighted average number of ordinary shares in the computation of diluted earnings per share | 4,429,553 | 4,429,553 | 4,392,013 | 4,347,670 |