XML 265 R155.htm IDEA: XBRL DOCUMENT v3.21.2
Employee Benefits - Summary of Sensitivity Analysis for Actuarial Assumptions (Parenthetical) (Detail)
Mar. 31, 2021
Mar. 31, 2020
Disclosure Of Sensitivity Analysis For Actuarial Assumptions [Abstract]    
Percentage of change in discount rate 1.00% 1.00%
Percentage of change in future salary growth 1.00% 1.00%
Percentage of change in withdrawal rate 10.00% 10.00%