v3.25.2
Fair Value - Assets and liabilities measured at fair value on a recurring basis (Details) - USD ($)
$ in Thousands
6 Months Ended
Jun. 30, 2025
Dec. 31, 2024
Assets    
Derivative financial instruments $ 211,000 $ 160,300
Trading securities 95,306 102,932
Securities available for sale 5,927,867 4,320,593
Liabilities    
Derivative financial instruments 611,300 878,000
U.S. Treasuries    
Assets    
Securities available for sale   10,656
U.S. Government agencies    
Assets    
Trading securities 12,908 15,002
Securities available for sale   150,418
Residential mortgage-backed securities issued by U.S. government agencies or sponsored enterprises    
Assets    
Trading securities 6,501 14,803
Securities available for sale 1,523,879 1,377,525
Commercial mortgage-backed securities issued by U.S. government agencies or sponsored enterprises    
Assets    
Trading securities 6,967 14,419
Securities available for sale 581,492 1,040,555
State and municipal obligations    
Assets    
Trading securities 20,228 35,896
Securities available for sale 922,417 945,723
Small Business Administration loan-backed securities    
Assets    
Trading securities 48,702 22,571
Securities available for sale 576,514 310,112
Corporate securities    
Assets    
Securities available for sale 26,594 26,509
Significant Other Observable Inputs (Level 2)    
Assets    
Mortgage loans held for sale 319,939 281,662
Trading securities 95,306 102,932
Significant Unobservable Inputs (Level 3)    
Assets    
Mortgage servicing rights 85,836 89,795
SBA servicing asset 5,801 6,028
Changes in fair value of assets    
Changes in hierarchy classifications of Level 3 assets 0  
Changes in hierarchy classifications of Level 3 liabilities 0  
Recurring basis    
Assets    
Derivative financial instruments 214,898 161,490
Mortgage loans held for sale 71,038 98,115
Trading securities 95,306 102,932
Securities available for sale 5,927,867 4,320,593
Mortgage servicing rights 85,836 89,795
SBA servicing asset 5,801 6,028
Fair value of Assets, Total 6,400,746 4,778,953
Liabilities    
Derivative financial instruments 612,284 879,855
Recurring basis | U.S. Treasuries    
Assets    
Securities available for sale   10,656
Recurring basis | U.S. Government agencies    
Assets    
Securities available for sale   150,418
Recurring basis | Residential mortgage-backed securities issued by U.S. government agencies or sponsored enterprises    
Assets    
Securities available for sale 1,523,879 1,377,525
Recurring basis | Residential Collateralized Mortgage-Obligations Issued By U.S. Government Agencies Or Sponsored Enterprises    
Assets    
Securities available for sale 2,296,971 459,095
Recurring basis | Commercial mortgage-backed securities issued by U.S. government agencies or sponsored enterprises    
Assets    
Securities available for sale 581,492 1,040,555
Recurring basis | State and municipal obligations    
Assets    
Securities available for sale 922,417 945,723
Recurring basis | Small Business Administration loan-backed securities    
Assets    
Securities available for sale 576,514 310,112
Recurring basis | Corporate securities    
Assets    
Securities available for sale 26,594 26,509
Recurring basis | Significant Other Observable Inputs (Level 2)    
Assets    
Derivative financial instruments 214,898 161,490
Mortgage loans held for sale 71,038 98,115
Trading securities 95,306 102,932
Securities available for sale 5,927,867 4,320,593
Fair value of Assets, Total 6,309,109 4,683,130
Liabilities    
Derivative financial instruments 612,284 879,855
Recurring basis | Significant Other Observable Inputs (Level 2) | U.S. Treasuries    
Assets    
Securities available for sale   10,656
Recurring basis | Significant Other Observable Inputs (Level 2) | U.S. Government agencies    
Assets    
Securities available for sale   150,418
Recurring basis | Significant Other Observable Inputs (Level 2) | Residential mortgage-backed securities issued by U.S. government agencies or sponsored enterprises    
Assets    
Securities available for sale 1,523,879 1,377,525
Recurring basis | Significant Other Observable Inputs (Level 2) | Residential Collateralized Mortgage-Obligations Issued By U.S. Government Agencies Or Sponsored Enterprises    
Assets    
Securities available for sale 2,296,971 459,095
Recurring basis | Significant Other Observable Inputs (Level 2) | Commercial mortgage-backed securities issued by U.S. government agencies or sponsored enterprises    
Assets    
Securities available for sale 581,492 1,040,555
Recurring basis | Significant Other Observable Inputs (Level 2) | State and municipal obligations    
Assets    
Securities available for sale 922,417 945,723
Recurring basis | Significant Other Observable Inputs (Level 2) | Small Business Administration loan-backed securities    
Assets    
Securities available for sale 576,514 310,112
Recurring basis | Significant Other Observable Inputs (Level 2) | Corporate securities    
Assets    
Securities available for sale 26,594 26,509
Recurring basis | Significant Unobservable Inputs (Level 3)    
Assets    
Mortgage servicing rights 85,836 89,795
SBA servicing asset 5,801 6,028
Fair value of Assets, Total 91,637 $ 95,823
Changes in fair value of assets    
Unrealized losses included in accumulated other comprehensive (loss) income related to Level 3 financial assets and liabilities 0  
Recurring basis | Significant Unobservable Inputs (Level 3) | Mortgage Servicing Rights    
Changes in fair value of assets    
Fair value of assets at the beginning of the period 89,795  
Servicing assets that resulted from transfers of financial assets 4,124  
Changes in fair value due to valuation inputs or assumptions $ (4,770)  
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] Revenue from Contract with Customer, Excluding Assessed Tax  
Changes in fair value due to decay $ (3,313)  
Fair value of assets at the end of the period 85,836  
Recurring basis | Significant Unobservable Inputs (Level 3) | SBA servicing asset    
Changes in fair value of assets    
Fair value of assets at the beginning of the period 6,028  
Servicing assets that resulted from transfers of financial assets 889  
Changes in fair value due to valuation inputs or assumptions $ 67  
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] Revenue from Contract with Customer, Excluding Assessed Tax  
Changes in fair value due to decay $ (1,183)  
Fair value of assets at the end of the period $ 5,801