XML 152 R136.htm IDEA: XBRL DOCUMENT v3.22.1
Investment Properties - Additional Information (Detail)
$ in Millions, $ in Millions
12 Months Ended
Dec. 31, 2021
TWD ($)
Dec. 31, 2021
USD ($)
Dec. 31, 2020
TWD ($)
Dec. 31, 2019
TWD ($)
Disclosure Of Investment Property [Abstract]        
Reversal of impairment loss $ 83 $ 3 $ 27 $ 57