v3.26.1
Regulation and Capital Adequacy - Risk-Based Capital and Leverage Ratios and "Well-capitalized" Requirements (Detail)
Mar. 31, 2026
Jan. 01, 2026
Dec. 31, 2025
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]      
Tier 1 leverage ratio 0.040   0.040
"Well-capitalized" Requirements, SLR 0.0375   0.050
G-SIB Surcharge 0.50 0.50  
SLR capped 0.01    
Minimum supplementary leverage ratio 0.03   0.03
Minimum supplementary leverage ratio, buffer 0.75%    
Advanced      
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]      
Total capital ratio 0.080   0.080
CET1 capital ratio 0.045   0.045
Tier 1 capital ratio 0.060   0.060
Capital conservation buffer 0.025   0.025
Counter-cyclical capital buffer 0   0
Standardized      
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]      
Total capital ratio 0.080   0.080
CET1 capital ratio 0.045   0.045
Tier 1 capital ratio 0.060   0.060
Counter-cyclical capital buffer 0   0
Reportable Legal Entities      
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]      
CET1 capital ratio 7.00%   7.00%
Tier 1 capital ratio 8.50%   8.50%
Total capital ratio 0.105   0.105
Tier 1 leverage ratio 0.040   0.040
Requirements, SLR 3.75%   3.00%
"Well Capitalized" Requirements, CET 1 capital ratio 0.065   0.065
"Well-capitalized" Requirements, Tier 1 capital ratio 0.080   0.080
"Well-capitalized" Requirements, Total capital ratio 0.100   0.100
"Well-capitalized" Requirements, Tier 1 leverage ratio 0.050   0.050
"Well-capitalized" Requirements, SLR     0.060
CET1 capital ratio 0.045   0.045
Tier 1 capital ratio 0.060   0.060
Minimum required capital ratio, advanced 8.00%   8.00%
Reportable Legal Entities | Advanced      
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]      
Capital conservation buffer 0.025   0.025
Reportable Legal Entities | Standardized      
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]      
Counter-cyclical capital buffer 0   0