v3.26.1
Fair value of financial instruments (Details) - USD ($)
$ in Thousands
Jun. 30, 2026
Dec. 31, 2025
Financial Assets:    
Cash and due from banks $ 365,013 $ 402,755
Money market investments 4,555,489 4,626,506
Debt securities available-for-sale 24,792,834 20,574,972
Debt securities held-to-maturity: 6,197,790 7,321,717
Equity securities:    
Total equity securities 236,674 229,848
Mortgage servicing rights 94,485 96,356
Deposits:    
Time deposits 9,905,076 9,479,361
Total deposits 70,233,115 66,190,093
Assets sold under agreements to repurchase 77,521 39,001
Other short-term borrowings 675,000 650,000
Notes payable:    
Total notes payable 710,310 759,577
U.S. Treasury securities    
Financial Assets:    
Debt securities available-for-sale 20,270,608 15,723,454
Debt securities held-to-maturity: 6,154,728 7,268,967
Obligations of Puerto Rico, States and political subdivisions    
Financial Assets:    
Debt securities held-to-maturity: 35,619 45,295
Collateralized mortgage obligations - federal agencies    
Financial Assets:    
Debt securities available-for-sale 89,533 100,241
Debt securities held-to-maturity: 1,483 1,495
Securities in wholly owned statutory business trusts    
Financial Assets:    
Debt securities held-to-maturity: 5,960 5,960
Carrying amount    
Financial Assets:    
Cash and due from banks 365,013 402,755
Money market investments 4,555,489 4,626,506
Trading account debt securities, excluding derivatives 31,168 36,569
Debt securities available-for-sale 24,792,835 20,574,972
Debt securities held-to-maturity: 6,197,790 7,321,717
Equity securities:    
FHLB stock 67,428 68,422
FRB stock 104,788 102,665
Other investments 64,458 58,761
Total equity securities 236,674 229,848
Loans held-for-sale 88,579 9,998
Loans held-in-portfolio 38,965,030 38,519,462
Mortgage servicing rights 94,485 96,356
Derivatives 28,518 27,913
Deposits:    
Demand deposits 60,328,037 56,710,732
Time deposits 9,905,078 9,479,361
Total deposits 70,233,115 66,190,093
Assets sold under agreements to repurchase 77,521 39,001
Other short-term borrowings 675,000 650,000
Notes payable:    
FHLB advances 114,620 164,620
Unsecured senior debt securities 397,277 396,558
Junior subordinated deferrable interest debentures (related to trust preferred securities) 198,413 198,399
Total notes payable 710,310 759,577
Derivatives 26,953 25,740
Carrying amount | U.S. Treasury securities    
Financial Assets:    
Debt securities held-to-maturity: 6,154,728 7,268,967
Carrying amount | Obligations of Puerto Rico, States and political subdivisions    
Financial Assets:    
Debt securities held-to-maturity: 35,619 45,295
Carrying amount | Collateralized mortgage obligations - federal agencies    
Financial Assets:    
Debt securities held-to-maturity: 1,483 1,495
Carrying amount | Securities in wholly owned statutory business trusts    
Financial Assets:    
Debt securities held-to-maturity: 5,960 5,960
Fair value    
Financial Assets:    
Cash and due from banks 365,013 402,755
Money market investments 4,555,489 4,626,506
Trading account debt securities, excluding derivatives 31,168 36,569
Debt securities available-for-sale 24,792,835 20,574,972
Debt securities held-to-maturity: 6,176,976 7,363,587
Equity securities:    
FHLB stock 67,428 68,422
FRB stock 104,788 102,665
Other investments 64,495 59,301
Total equity securities 236,711 230,388
Loans held-for-sale 88,579 9,998
Loans held-in-portfolio 38,117,234 37,858,044
Mortgage servicing rights 94,485 96,356
Derivatives 28,518 27,913
Deposits:    
Demand deposits 60,328,037 56,710,732
Time deposits 9,672,021 9,305,980
Total deposits 70,000,058 66,016,712
Assets sold under agreements to repurchase 106,441 39,004
Other short-term borrowings 675,000 650,000
Notes payable:    
FHLB advances 112,942 163,417
Unsecured senior debt securities 414,004 419,300
Junior subordinated deferrable interest debentures (related to trust preferred securities) 198,452 191,909
Total notes payable 725,398 774,626
Derivatives 26,953 25,740
Fair value | U.S. Treasury securities    
Financial Assets:    
Debt securities held-to-maturity: 6,133,383 7,309,991
Fair value | Obligations of Puerto Rico, States and political subdivisions    
Financial Assets:    
Debt securities held-to-maturity: 36,338 46,330
Fair value | Collateralized mortgage obligations - federal agencies    
Financial Assets:    
Debt securities held-to-maturity: 1,295 1,306
Fair value | Securities in wholly owned statutory business trusts    
Financial Assets:    
Debt securities held-to-maturity: 5,960 5,960
Fair value | Level 1    
Financial Assets:    
Cash and due from banks 365,013 402,755
Money market investments 4,545,508 4,616,272
Trading account debt securities, excluding derivatives 3,405 12,450
Debt securities available-for-sale 10,040,663 6,576,313
Debt securities held-to-maturity: 0 0
Equity securities:    
FHLB stock 0 0
FRB stock 0 0
Other investments 0 0
Total equity securities 0 0
Loans held-for-sale 0 0
Loans held-in-portfolio 0 0
Mortgage servicing rights 0 0
Derivatives 0 0
Deposits:    
Demand deposits 0
Time deposits 0
Total deposits 0 0
Assets sold under agreements to repurchase 0 0
Other short-term borrowings 0 0
Notes payable:    
FHLB advances 0 0
Unsecured senior debt securities 0 0
Junior subordinated deferrable interest debentures (related to trust preferred securities) 0 0
Total notes payable 0 0
Derivatives 0 0
Fair value | Level 1 | U.S. Treasury securities    
Financial Assets:    
Debt securities held-to-maturity: 0 0
Fair value | Level 1 | Obligations of Puerto Rico, States and political subdivisions    
Financial Assets:    
Debt securities held-to-maturity: 0 0
Fair value | Level 1 | Collateralized mortgage obligations - federal agencies    
Financial Assets:    
Debt securities held-to-maturity: 0 0
Fair value | Level 1 | Securities in wholly owned statutory business trusts    
Financial Assets:    
Debt securities held-to-maturity: 0 0
Fair value | Level 2    
Financial Assets:    
Cash and due from banks 0 0
Money market investments 9,981 10,234
Trading account debt securities, excluding derivatives 27,590 23,936
Debt securities available-for-sale 14,751,294 13,997,504
Debt securities held-to-maturity: 6,140,638 7,324,023
Equity securities:    
FHLB stock 67,428 68,422
FRB stock 104,788 102,665
Other investments 56,041 50,632
Total equity securities 228,257 221,719
Loans held-for-sale 88,579 9,998
Loans held-in-portfolio 0 0
Mortgage servicing rights 0 0
Derivatives 28,518 27,913
Deposits:    
Demand deposits 60,328,037 56,710,732
Time deposits 9,672,021 9,305,980
Total deposits 70,000,058 66,016,712
Assets sold under agreements to repurchase 106,441 39,004
Other short-term borrowings 675,000 650,000
Notes payable:    
FHLB advances 112,942 163,417
Unsecured senior debt securities 414,004 419,300
Junior subordinated deferrable interest debentures (related to trust preferred securities) 198,452 191,909
Total notes payable 725,398 774,626
Derivatives 26,953 25,740
Fair value | Level 2 | U.S. Treasury securities    
Financial Assets:    
Debt securities held-to-maturity: 6,133,383 7,309,991
Fair value | Level 2 | Obligations of Puerto Rico, States and political subdivisions    
Financial Assets:    
Debt securities held-to-maturity: 0 6,766
Fair value | Level 2 | Collateralized mortgage obligations - federal agencies    
Financial Assets:    
Debt securities held-to-maturity: 1,295 1,306
Fair value | Level 2 | Securities in wholly owned statutory business trusts    
Financial Assets:    
Debt securities held-to-maturity: 5,960 5,960
Fair value | Level 3    
Financial Assets:    
Cash and due from banks 0 0
Money market investments 0 0
Trading account debt securities, excluding derivatives 173 183
Debt securities available-for-sale 878 1,155
Debt securities held-to-maturity: 36,338 39,564
Equity securities:    
FHLB stock 0 0
FRB stock 0 0
Other investments 7,068 7,817
Total equity securities 7,068 7,817
Loans held-for-sale 0 0
Loans held-in-portfolio 38,117,234 37,858,044
Mortgage servicing rights 94,485 96,356
Derivatives 0 0
Deposits:    
Demand deposits 0 0
Time deposits 0 0
Total deposits 0 0
Assets sold under agreements to repurchase 0 0
Other short-term borrowings 0 0
Notes payable:    
FHLB advances 0 0
Unsecured senior debt securities 0 0
Junior subordinated deferrable interest debentures (related to trust preferred securities) 0 0
Total notes payable 0 0
Derivatives 0 0
Fair value | Level 3 | U.S. Treasury securities    
Financial Assets:    
Debt securities held-to-maturity: 0 0
Fair value | Level 3 | Obligations of Puerto Rico, States and political subdivisions    
Financial Assets:    
Debt securities held-to-maturity: 36,338 39,564
Fair value | Level 3 | Collateralized mortgage obligations - federal agencies    
Financial Assets:    
Debt securities held-to-maturity: 0 0
Fair value | Level 3 | Securities in wholly owned statutory business trusts    
Financial Assets:    
Debt securities held-to-maturity: 0 0
Fair value | Measured at NAV    
Financial Assets:    
Cash and due from banks 0 0
Money market investments 0 0
Trading account debt securities, excluding derivatives 0 0
Debt securities available-for-sale 0 0
Debt securities held-to-maturity: 0 0
Equity securities:    
FHLB stock 0 0
FRB stock 0 0
Other investments 1,386 852
Total equity securities 1,386 852
Loans held-for-sale 0 0
Loans held-in-portfolio 0 0
Mortgage servicing rights 0 0
Derivatives 0 0
Deposits:    
Demand deposits 0 0
Time deposits 0 0
Total deposits 0 0
Assets sold under agreements to repurchase 0 0
Other short-term borrowings 0 0
Notes payable:    
FHLB advances 0 0
Unsecured senior debt securities 0 0
Junior subordinated deferrable interest debentures (related to trust preferred securities) 0 0
Total notes payable 0 0
Derivatives 0 0
Fair value | Measured at NAV | U.S. Treasury securities    
Financial Assets:    
Debt securities held-to-maturity: 0 0
Fair value | Measured at NAV | Obligations of Puerto Rico, States and political subdivisions    
Financial Assets:    
Debt securities held-to-maturity: 0 0
Fair value | Measured at NAV | Collateralized mortgage obligations - federal agencies    
Financial Assets:    
Debt securities held-to-maturity: 0 0
Fair value | Measured at NAV | Securities in wholly owned statutory business trusts    
Financial Assets:    
Debt securities held-to-maturity: $ 0 $ 0