v3.26.1
Critical Accounting Estimates and Judgments - Summary of Probability Weightings of Each Scenario (Detail)
12 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Upside [Member]    
Disclosure Of Detailed Information Of Probability Weightings Of Each Scenario The Group Estimates [Line Items]    
GDP Weighted Probability Rate 20.00% 20.00%
Base [Member]    
Disclosure Of Detailed Information Of Probability Weightings Of Each Scenario The Group Estimates [Line Items]    
GDP Weighted Probability Rate 60.00% 60.00%
Downside [Member]    
Disclosure Of Detailed Information Of Probability Weightings Of Each Scenario The Group Estimates [Line Items]    
GDP Weighted Probability Rate 18.00% 19.00%
Severe Downside [Member]    
Disclosure Of Detailed Information Of Probability Weightings Of Each Scenario The Group Estimates [Line Items]    
GDP Weighted Probability Rate 2.00% 1.00%