v3.25.2
Fair Value Accounting - Schedule of Assets and Liabilities Measured at Estimated Fair Value on a Recurring Basis (Details) - USD ($)
$ in Thousands
Jun. 30, 2025
Dec. 31, 2024
Assets    
Investment securities available for sale $ 7,798,824 $ 7,551,018
Mortgage loans held for sale 45,136 33,448
Derivatives Not Designated as Hedging Instruments    
Liabilities    
Estimated fair value of derivative liabilities 134,690 201,917
Visa derivative | Derivatives Not Designated as Hedging Instruments    
Liabilities    
Estimated fair value of derivative liabilities 62 64
U.S. Treasury securities    
Assets    
Investment securities available for sale 1,240,926 1,212,742
Mortgage-backed securities issued by U.S. Government agencies    
Assets    
Investment securities available for sale 1,456,888 1,462,790
Mortgage-backed securities issued by U.S. Government sponsored enterprises    
Assets    
Investment securities available for sale 2,041,389 2,034,035
Collateralized mortgage obligations issued by U.S. Government sponsored enterprises    
Assets    
Investment securities available for sale 535,669 550,201
Commercial mortgage-backed securities issued by U.S. Government agencies or sponsored enterprises    
Assets    
Investment securities available for sale 2,485,074 2,253,116
Corporate debt securities and other debt securities    
Assets    
Investment securities available for sale 9,167 8,971
Level 1    
Assets    
Trading securities 4,000 0
Investment securities available for sale 1,240,926 1,212,742
Other investments 0 0
Mutual funds and mutual funds held in rabbi trusts 69,686 63,371
Derivative assets 0 0
Liabilities    
Mutual funds held in rabbi trusts 54,318 48,351
Derivative liabilities 0 0
Level 2    
Assets    
Trading securities 11,475 9,713
Investment securities available for sale 6,557,898 6,338,276
Other investments 0 0
Mutual funds and mutual funds held in rabbi trusts 0 0
Derivative assets 82,664 83,895
Liabilities    
Mutual funds held in rabbi trusts 0 0
Derivative liabilities 134,644 216,325
Level 3    
Assets    
Trading securities 0 0
Investment securities available for sale 0 0
Other investments 16,899 14,831
Mutual funds and mutual funds held in rabbi trusts 0 0
Derivative assets 0 0
Liabilities    
Mutual funds held in rabbi trusts 0 0
Derivative liabilities 0 0
Fair Value, Measurements, Recurring Basis    
Assets    
Trading securities 15,475 9,713
Investment securities available for sale 7,798,824 7,551,018
Mortgage loans held for sale 45,136 33,448
Other investments 16,899 14,831
Mutual funds and mutual funds held in rabbi trusts 69,686 63,371
Derivative assets 82,664 83,895
Liabilities    
Mutual funds held in rabbi trusts 54,318 48,351
Derivative liabilities 134,644 216,325
Fair Value, Measurements, Recurring Basis | U.S. Treasury securities    
Assets    
Trading securities 4,000 0
Investment securities available for sale 1,240,926 1,212,742
Fair Value, Measurements, Recurring Basis | State and municipal securities    
Assets    
Trading securities 59 473
Fair Value, Measurements, Recurring Basis | Asset-backed securities    
Assets    
Trading securities 11,312 9,240
Fair Value, Measurements, Recurring Basis | Other Investments    
Assets    
Trading securities 104 0
Fair Value, Measurements, Recurring Basis | U.S. Government agency securities    
Assets    
Investment securities available for sale 29,711 29,163
Fair Value, Measurements, Recurring Basis | Mortgage-backed securities issued by U.S. Government agencies    
Assets    
Investment securities available for sale 1,456,888 1,462,790
Fair Value, Measurements, Recurring Basis | Mortgage-backed securities issued by U.S. Government sponsored enterprises    
Assets    
Investment securities available for sale 2,041,389 2,034,035
Fair Value, Measurements, Recurring Basis | Collateralized mortgage obligations issued by U.S. Government sponsored enterprises    
Assets    
Investment securities available for sale 535,669 550,201
Fair Value, Measurements, Recurring Basis | Commercial mortgage-backed securities issued by U.S. Government agencies or sponsored enterprises    
Assets    
Investment securities available for sale 2,485,074 2,253,116
Fair Value, Measurements, Recurring Basis | Corporate debt securities and other debt securities    
Assets    
Investment securities available for sale 9,167 8,971
Fair Value, Measurements, Recurring Basis | Level 1    
Assets    
Trading securities 4,000 0
Investment securities available for sale 1,240,926 1,212,742
Mortgage loans held for sale 0 0
Other investments 0 0
Mutual funds and mutual funds held in rabbi trusts 69,686 63,371
Derivative assets 0 0
Liabilities    
Mutual funds held in rabbi trusts 54,318 48,351
Derivative liabilities 0 0
Fair Value, Measurements, Recurring Basis | Level 1 | U.S. Treasury securities    
Assets    
Trading securities 4,000 0
Investment securities available for sale 1,240,926 1,212,742
Fair Value, Measurements, Recurring Basis | Level 1 | State and municipal securities    
Assets    
Trading securities 0 0
Fair Value, Measurements, Recurring Basis | Level 1 | Asset-backed securities    
Assets    
Trading securities 0 0
Fair Value, Measurements, Recurring Basis | Level 1 | Other Investments    
Assets    
Trading securities 0 0
Fair Value, Measurements, Recurring Basis | Level 1 | U.S. Government agency securities    
Assets    
Investment securities available for sale 0 0
Fair Value, Measurements, Recurring Basis | Level 1 | Mortgage-backed securities issued by U.S. Government agencies    
Assets    
Investment securities available for sale 0 0
Fair Value, Measurements, Recurring Basis | Level 1 | Mortgage-backed securities issued by U.S. Government sponsored enterprises    
Assets    
Investment securities available for sale 0 0
Fair Value, Measurements, Recurring Basis | Level 1 | Collateralized mortgage obligations issued by U.S. Government sponsored enterprises    
Assets    
Investment securities available for sale 0 0
Fair Value, Measurements, Recurring Basis | Level 1 | Commercial mortgage-backed securities issued by U.S. Government agencies or sponsored enterprises    
Assets    
Investment securities available for sale 0 0
Fair Value, Measurements, Recurring Basis | Level 1 | Corporate debt securities and other debt securities    
Assets    
Investment securities available for sale 0 0
Fair Value, Measurements, Recurring Basis | Level 2    
Assets    
Trading securities 11,475 9,713
Investment securities available for sale 6,557,898 6,338,276
Mortgage loans held for sale 45,136 33,448
Other investments 0 0
Mutual funds and mutual funds held in rabbi trusts 0 0
Derivative assets 82,664 83,895
Liabilities    
Mutual funds held in rabbi trusts 0 0
Derivative liabilities 134,644 216,325
Fair Value, Measurements, Recurring Basis | Level 2 | U.S. Treasury securities    
Assets    
Trading securities 0 0
Investment securities available for sale 0 0
Fair Value, Measurements, Recurring Basis | Level 2 | State and municipal securities    
Assets    
Trading securities 59 473
Fair Value, Measurements, Recurring Basis | Level 2 | Asset-backed securities    
Assets    
Trading securities 11,312 9,240
Fair Value, Measurements, Recurring Basis | Level 2 | Other Investments    
Assets    
Trading securities 104 0
Fair Value, Measurements, Recurring Basis | Level 2 | U.S. Government agency securities    
Assets    
Investment securities available for sale 29,711 29,163
Fair Value, Measurements, Recurring Basis | Level 2 | Mortgage-backed securities issued by U.S. Government agencies    
Assets    
Investment securities available for sale 1,456,888 1,462,790
Fair Value, Measurements, Recurring Basis | Level 2 | Mortgage-backed securities issued by U.S. Government sponsored enterprises    
Assets    
Investment securities available for sale 2,041,389 2,034,035
Fair Value, Measurements, Recurring Basis | Level 2 | Collateralized mortgage obligations issued by U.S. Government sponsored enterprises    
Assets    
Investment securities available for sale 535,669 550,201
Fair Value, Measurements, Recurring Basis | Level 2 | Commercial mortgage-backed securities issued by U.S. Government agencies or sponsored enterprises    
Assets    
Investment securities available for sale 2,485,074 2,253,116
Fair Value, Measurements, Recurring Basis | Level 2 | Corporate debt securities and other debt securities    
Assets    
Investment securities available for sale 9,167 8,971
Fair Value, Measurements, Recurring Basis | Level 3    
Assets    
Trading securities 0 0
Investment securities available for sale 0 0
Mortgage loans held for sale 0 0
Other investments 16,899 14,831
Mutual funds and mutual funds held in rabbi trusts 0 0
Derivative assets 0 0
Liabilities    
Mutual funds held in rabbi trusts 0 0
Derivative liabilities 0 0
Fair Value, Measurements, Recurring Basis | Level 3 | U.S. Treasury securities    
Assets    
Trading securities 0 0
Investment securities available for sale 0 0
Fair Value, Measurements, Recurring Basis | Level 3 | State and municipal securities    
Assets    
Trading securities 0 0
Fair Value, Measurements, Recurring Basis | Level 3 | Asset-backed securities    
Assets    
Trading securities 0 0
Fair Value, Measurements, Recurring Basis | Level 3 | Other Investments    
Assets    
Trading securities 0 0
Fair Value, Measurements, Recurring Basis | Level 3 | U.S. Government agency securities    
Assets    
Investment securities available for sale 0 0
Fair Value, Measurements, Recurring Basis | Level 3 | Mortgage-backed securities issued by U.S. Government agencies    
Assets    
Investment securities available for sale 0 0
Fair Value, Measurements, Recurring Basis | Level 3 | Mortgage-backed securities issued by U.S. Government sponsored enterprises    
Assets    
Investment securities available for sale 0 0
Fair Value, Measurements, Recurring Basis | Level 3 | Collateralized mortgage obligations issued by U.S. Government sponsored enterprises    
Assets    
Investment securities available for sale 0 0
Fair Value, Measurements, Recurring Basis | Level 3 | Commercial mortgage-backed securities issued by U.S. Government agencies or sponsored enterprises    
Assets    
Investment securities available for sale 0 0
Fair Value, Measurements, Recurring Basis | Level 3 | Corporate debt securities and other debt securities    
Assets    
Investment securities available for sale $ 0 $ 0