Fair Value Measurements - Carrying Values and Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
ASSETS
Securities available for sale	$ 987,659	$ 987,591
Portfolio loans, net	7,978,779	7,641,464
Derivative financial assets	33,750	60,890
LIABILITIES
Junior subordinated debt securities	49,478	49,418	$ 49,358
Derivative financial liabilities	36,014	70,860
Interest rate swaps - commercial loans
ASSETS
Derivative financial assets	33,669	60,890
LIABILITIES
Derivative financial liabilities	36,014	70,860
Carrying Value
ASSETS
Cash and due from banks, including interest-bearing deposits	163,436	244,820
Securities available for sale	987,659	987,591
Loans held for sale	1,010
Portfolio loans, net	7,978,779	7,641,464
Collateral receivable	2	2,034
Securities held in a deferred compensation plan	14,212	10,876
Mortgage servicing rights	5,034	5,646
LIABILITIES
Deposits	7,958,831	7,783,117
Collateral payable	26,964	52,516
Short-term borrowings	165,000	150,000
Long-term borrowings	50,815	50,896
Junior subordinated debt securities	49,478	49,418
Carrying Value \| Interest rate swap contracts - commercial loans
ASSETS
Derivative financial assets	33,669
LIABILITIES
Derivative financial liabilities	33,990	61,271
Carrying Value \| Interest rate swap contracts - cash flow hedge
LIABILITIES
Derivative financial liabilities	2,024	9,589
Carrying Value \| Interest rate lock commitments - mortgage loans
ASSETS
Derivative financial assets	81
Carrying Value \| Interest rate swaps - commercial loans
ASSETS
Derivative financial assets		60,890
Fair Value Measurements
ASSETS
Cash and due from banks, including interest-bearing deposits	163,436	244,820
Securities available for sale	987,659	987,591
Loans held for sale	1,010
Portfolio loans, net	7,807,824	7,362,898
Collateral receivable	2	2,034
Securities held in a deferred compensation plan	14,212	10,876
Mortgage servicing rights	8,034	8,533
LIABILITIES
Deposits	7,956,632	7,778,740
Collateral payable	26,964	52,516
Short-term borrowings	165,000	150,000
Long-term borrowings	50,856	50,652
Junior subordinated debt securities	49,478	49,418
Fair Value Measurements \| Interest rate swap contracts - commercial loans
ASSETS
Derivative financial assets	33,669
LIABILITIES
Derivative financial liabilities	33,990	61,271
Fair Value Measurements \| Interest rate swap contracts - cash flow hedge
LIABILITIES
Derivative financial liabilities	2,024	9,589
Fair Value Measurements \| Interest rate lock commitments - mortgage loans
ASSETS
Derivative financial assets	81
Fair Value Measurements \| Interest rate swaps - commercial loans
ASSETS
Derivative financial assets		60,890
Fair Value Measurements \| Level 1
ASSETS
Cash and due from banks, including interest-bearing deposits	163,436	244,820
Securities available for sale	85,889	93,944
Loans held for sale	0
Portfolio loans, net	0	0
Collateral receivable	2	2,034
Securities held in a deferred compensation plan	14,212	10,876
Mortgage servicing rights	0	0
LIABILITIES
Deposits	6,010,039	5,916,154
Collateral payable	26,964	52,516
Short-term borrowings	0	0
Long-term borrowings	0	0
Junior subordinated debt securities	0	0
Fair Value Measurements \| Level 1 \| Interest rate swap contracts - commercial loans
ASSETS
Derivative financial assets	0
LIABILITIES
Derivative financial liabilities	0	0
Fair Value Measurements \| Level 1 \| Interest rate swap contracts - cash flow hedge
LIABILITIES
Derivative financial liabilities	0	0
Fair Value Measurements \| Level 1 \| Interest rate lock commitments - mortgage loans
ASSETS
Derivative financial assets	0
Fair Value Measurements \| Level 1 \| Interest rate swaps - commercial loans
ASSETS
Derivative financial assets		0
Fair Value Measurements \| Level 2
ASSETS
Cash and due from banks, including interest-bearing deposits	0	0
Securities available for sale	901,770	893,647
Loans held for sale	1,010
Portfolio loans, net	0	0
Collateral receivable	0	0
Securities held in a deferred compensation plan	0	0
Mortgage servicing rights	0	0
LIABILITIES
Deposits	1,946,593	1,862,586
Collateral payable	0	0
Short-term borrowings	165,000	150,000
Long-term borrowings	50,856	50,652
Junior subordinated debt securities	49,478	49,418
Fair Value Measurements \| Level 2 \| Interest rate swap contracts - commercial loans
ASSETS
Derivative financial assets	33,669
LIABILITIES
Derivative financial liabilities	33,990	61,271
Fair Value Measurements \| Level 2 \| Interest rate swap contracts - cash flow hedge
LIABILITIES
Derivative financial liabilities	2,024	9,589
Fair Value Measurements \| Level 2 \| Interest rate lock commitments - mortgage loans
ASSETS
Derivative financial assets	0
Fair Value Measurements \| Level 2 \| Interest rate swaps - commercial loans
ASSETS
Derivative financial assets		60,890
Fair Value Measurements \| Level 3
ASSETS
Cash and due from banks, including interest-bearing deposits	0	0
Securities available for sale	0	0
Loans held for sale
Portfolio loans, net	7,807,824	7,362,898
Collateral receivable	0	0
Securities held in a deferred compensation plan	0	0
Mortgage servicing rights	8,034	8,533
LIABILITIES
Deposits	0	0
Collateral payable	0	0
Short-term borrowings	0	0
Long-term borrowings	0	0
Junior subordinated debt securities	0	0
Fair Value Measurements \| Level 3 \| Interest rate swap contracts - commercial loans
ASSETS
Derivative financial assets	0
LIABILITIES
Derivative financial liabilities	0	0
Fair Value Measurements \| Level 3 \| Interest rate swap contracts - cash flow hedge
LIABILITIES
Derivative financial liabilities	0	0
Fair Value Measurements \| Level 3 \| Interest rate lock commitments - mortgage loans
ASSETS
Derivative financial assets	$ 81
Fair Value Measurements \| Level 3 \| Interest rate swaps - commercial loans
ASSETS
Derivative financial assets		$ 0

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