v3.26.1
Fair Value - Carrying Amounts and Estimated Fair Values of Financial Instruments (Details) - USD ($)
$ in Thousands
Jun. 30, 2026
Dec. 31, 2025
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Securities held to maturity $ 1,134,823 $ 1,207,454
Net LHFI 13,764,834 13,517,162
Deposits 16,071,215 15,499,784
Federal funds purchased and securities sold under repurchase agreements 360,000 445,000
Other borrowings 137,853 364,762
Subordinated notes 172,119 171,966
Junior subordinated debt securities 61,856 61,856
Level 2 [Member] | Carrying Value [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Cash and short-term investments 669,892 668,007
Securities held to maturity 1,134,823 1,207,454
Deposits 16,071,215 15,499,784
Federal funds purchased and securities sold under repurchase agreements 360,000 445,000
Other borrowings 137,853 364,762
Subordinated notes 172,119 171,966
Junior subordinated debt securities 61,856 61,856
Level 2 [Member] | Estimate Fair Value [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Cash and short-term investments 669,892 668,007
Securities held to maturity 1,096,876 1,180,569
Deposits 16,060,968 15,494,681
Federal funds purchased and securities sold under repurchase agreements 360,000 445,000
Other borrowings 137,853 364,762
Subordinated notes 174,563 176,750
Junior subordinated debt securities 52,578 52,964
Level 3 [Member] | Carrying Value [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Net LHFI 13,764,834 13,517,162
Level 3 [Member] | Estimate Fair Value [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Net LHFI $ 13,728,828 $ 13,544,873