Fair Value Measurements - Carrying Values and Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
ASSETS
Securities available for sale	$ 1,001,149	$ 987,591
Portfolio loans, net	7,882,852	7,641,464
Derivative financial assets	35,758	60,890
LIABILITIES
Junior subordinated debt securities	49,463	49,418
Derivative financial liabilities	39,241	70,860
Carrying Value
ASSETS
Cash and due from banks, including interest-bearing deposits	196,228	244,820
Securities available for sale	1,001,149	987,591
Portfolio loans, net	7,882,852	7,641,464
Collateral receivable	608	2,034
Securities held in a deferred compensation plan	13,609	10,876
Mortgage servicing rights	5,149	5,646
LIABILITIES
Deposits	7,921,943	7,783,117
Collateral payable	22,660	52,516
Short-term borrowings	135,000	150,000
Long-term borrowings	50,836	50,896
Junior subordinated debt securities	49,463	49,418
Carrying Value \| Interest rate swaps - commercial loans
ASSETS
Derivative financial assets		60,890
Carrying Value \| Interest rate swap contracts - commercial loans
ASSETS
Derivative financial assets	35,739
LIABILITIES
Derivative financial liabilities	36,042	61,271
Carrying Value \| Interest rate swap contracts - cash flow hedge
LIABILITIES
Derivative financial liabilities	3,199	9,589
Carrying Value \| Interest rate lock commitments - mortgage loans
ASSETS
Derivative financial assets	19
Fair Value Measurements
ASSETS
Cash and due from banks, including interest-bearing deposits	196,228	244,820
Securities available for sale	1,001,149	987,591
Portfolio loans, net	7,704,463	7,362,898
Collateral receivable	608	2,034
Securities held in a deferred compensation plan	13,609	10,876
Mortgage servicing rights	8,006	8,533
LIABILITIES
Deposits	7,918,559	7,778,740
Collateral payable	22,660	52,516
Short-term borrowings	135,000	150,000
Long-term borrowings	50,848	50,652
Junior subordinated debt securities	49,463	49,418
Fair Value Measurements \| Interest rate swaps - commercial loans
ASSETS
Derivative financial assets		60,890
Fair Value Measurements \| Interest rate swap contracts - commercial loans
ASSETS
Derivative financial assets	35,739
LIABILITIES
Derivative financial liabilities	36,042	61,271
Fair Value Measurements \| Interest rate swap contracts - cash flow hedge
LIABILITIES
Derivative financial liabilities	3,199	9,589
Fair Value Measurements \| Interest rate lock commitments - mortgage loans
ASSETS
Derivative financial assets	19
Fair Value Measurements \| Level 1
ASSETS
Cash and due from banks, including interest-bearing deposits	196,228	244,820
Securities available for sale	95,581	93,944
Portfolio loans, net	0	0
Collateral receivable	608	2,034
Securities held in a deferred compensation plan	13,609	10,876
Mortgage servicing rights	0	0
LIABILITIES
Deposits	5,997,324	5,916,154
Collateral payable	22,660	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 swaps - commercial loans
ASSETS
Derivative financial assets		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 2
ASSETS
Cash and due from banks, including interest-bearing deposits	0	0
Securities available for sale	905,568	893,647
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	1,921,235	1,862,586
Collateral payable	0	0
Short-term borrowings	135,000	150,000
Long-term borrowings	50,848	50,652
Junior subordinated debt securities	49,463	49,418
Fair Value Measurements \| Level 2 \| Interest rate swaps - commercial loans
ASSETS
Derivative financial assets		60,890
Fair Value Measurements \| Level 2 \| Interest rate swap contracts - commercial loans
ASSETS
Derivative financial assets	35,739
LIABILITIES
Derivative financial liabilities	36,042	61,271
Fair Value Measurements \| Level 2 \| Interest rate swap contracts - cash flow hedge
LIABILITIES
Derivative financial liabilities	3,199	9,589
Fair Value Measurements \| Level 2 \| Interest rate lock commitments - mortgage loans
ASSETS
Derivative financial assets	0
Fair Value Measurements \| Level 3
ASSETS
Cash and due from banks, including interest-bearing deposits	0	0
Securities available for sale	0	0
Portfolio loans, net	7,704,463	7,362,898
Collateral receivable	0	0
Securities held in a deferred compensation plan	0	0
Mortgage servicing rights	8,006	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 swaps - commercial loans
ASSETS
Derivative financial assets		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	$ 19

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