v3.26.1
Commitments and contingencies - Additional Information (Details) - USD ($)
 6 Months Ended 12 Months Ended
Jun. 30, 2026
Dec. 31, 2025
Direct Exposure To The Puerto Rico Government [Line Items]    
Maximum automated clearing house transaction settlement exposure $ 47,400,000  
Loans HIP 39,749,862,000 $ 39,327,518,000
Minimum    
Direct Exposure To The Puerto Rico Government [Line Items]    
Legal proceedings 0  
Maximum    
Direct Exposure To The Puerto Rico Government [Line Items]    
Legal proceedings 11,300,000  
BVI    
Direct Exposure To The Puerto Rico Government [Line Items]    
Total exposure 0  
PR Government Direct Exposure    
Direct Exposure To The Puerto Rico Government [Line Items]    
Total exposure 464,096,000 391,300,000
Total outstanding $ 414,696,000 342,900,000
Percentage of exposure municipal loans and securities 81.00%  
PR Government Indirect Exposure    
Direct Exposure To The Puerto Rico Government [Line Items]    
Total outstanding $ 199,700,000 209,300,000
Loans and leases receivable 164,900,000 166,900,000
PR Government Indirect Exposure | Corporate Bonds and Debentures    
Direct Exposure To The Puerto Rico Government [Line Items]    
Total outstanding 34,800,000 35,500,000
USVI Government Direct Exposure | USVI Government And Public Corporations    
Direct Exposure To The Puerto Rico Government [Line Items]    
Total exposure 28,300,000 28,300,000
Commitments to extend credit:    
Direct Exposure To The Puerto Rico Government [Line Items]    
Reserve of potential losses associated with unfunded loan commitments 14,900,000 14,400,000
Noncredit Commitment    
Direct Exposure To The Puerto Rico Government [Line Items]    
Investments 5,100,000 6,800,000
Loans | PR Government Direct Exposure    
Direct Exposure To The Puerto Rico Government [Line Items]    
Total outstanding 407,574,000 333,200,000
Investment Portfolio | PR Government Direct Exposure    
Direct Exposure To The Puerto Rico Government [Line Items]    
Total outstanding 7,122,000 8,800,000
Residential Mortgage Loans | Guaranteed U.S. Government    
Direct Exposure To The Puerto Rico Government [Line Items]    
Loans HIP 2,700,000,000 2,500,000,000
Commercial | Guaranteed U.S. Government    
Direct Exposure To The Puerto Rico Government [Line Items]    
Loans HIP 84,300,000 80,500,000
Retail and Commerical Loans | BVI    
Direct Exposure To The Puerto Rico Government [Line Items]    
Loans HIP $ 197,600,000 $ 195,300,000