XML 162 R148.htm IDEA: XBRL DOCUMENT v3.24.1.u1
Retirement Benefit Plans - Pension Costs Recognized in Profit and Loss for Defined Benefit Plans (Detail) - TWD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Disclosure Of Defined Plan [line items]      
Defined benefit plans pension costs recognized in profit and loss $ 935 $ 1,048 $ 1,216
Operating costs [Member]      
Disclosure Of Defined Plan [line items]      
Defined benefit plans pension costs recognized in profit and loss 488 565 725
Marketing expenses [Member]      
Disclosure Of Defined Plan [line items]      
Defined benefit plans pension costs recognized in profit and loss 334 360 367
General and administrative expenses [Member]      
Disclosure Of Defined Plan [line items]      
Defined benefit plans pension costs recognized in profit and loss 78 86 80
Research and development expenses [Member]      
Disclosure Of Defined Plan [line items]      
Defined benefit plans pension costs recognized in profit and loss $ 35 $ 37 $ 44