Fair Value Measurements - Carrying Values and Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
ASSETS
Securities available for sale	$ 987,591	$ 970,391
Portfolio loans, net	7,641,464	7,545,375
Derivative financial assets	60,890	63,018
LIABILITIES
Junior subordinated debt securities	49,418	49,358	$ 54,453
Derivative financial liabilities	70,860	78,293
Carrying Value
ASSETS
Cash and due from banks, including interest-bearing deposits	244,820	233,612
Securities available for sale	987,591	970,391
Loans held for sale		153
Portfolio loans, net	7,641,464	7,545,375
Collateral receivable	2,034	5,356
Securities held in a deferred compensation plan	10,876	9,399
Mortgage servicing rights	5,646	6,345
LIABILITIES
Deposits	7,783,117	7,521,769
Collateral payable	52,516	50,920
Short-term borrowings	150,000	415,000
Long-term borrowings	50,896	39,277
Junior subordinated debt securities	49,418	49,358
Carrying Value \| Interest rate swap contracts - commercial loans
ASSETS
Derivative financial assets	60,890
LIABILITIES
Derivative financial liabilities	61,271	63,554
Carrying Value \| Interest rate swap contracts—commercial loans
ASSETS
Derivative financial assets		63,018
Carrying Value \| Interest rate swap contracts - cash flow hedge
LIABILITIES
Derivative financial liabilities	9,589	14,739
Fair Value Measurements
ASSETS
Cash and due from banks, including interest-bearing deposits	244,820	233,612
Securities available for sale	987,591	970,391
Loans held for sale		153
Portfolio loans, net	7,362,898	7,263,270
Collateral receivable	2,034	5,356
Securities held in a deferred compensation plan	10,876	9,399
Mortgage servicing rights	8,533	8,704
LIABILITIES
Deposits	7,778,740	7,511,598
Collateral payable	52,516	50,920
Short-term borrowings	150,000	415,000
Long-term borrowings	50,652	38,995
Junior subordinated debt securities	49,418	49,358
Fair Value Measurements \| Interest rate swap contracts - commercial loans
ASSETS
Derivative financial assets	60,890
LIABILITIES
Derivative financial liabilities	61,271	63,554
Fair Value Measurements \| Interest rate swap contracts—commercial loans
ASSETS
Derivative financial assets		63,018
Fair Value Measurements \| Interest rate swap contracts - cash flow hedge
LIABILITIES
Derivative financial liabilities	9,589	14,739
Fair Value Measurements \| Level 1
ASSETS
Cash and due from banks, including interest-bearing deposits	244,820	233,612
Securities available for sale	93,944	134,796
Loans held for sale		0
Portfolio loans, net	0	0
Collateral receivable	2,034	5,356
Securities held in a deferred compensation plan	10,876	9,399
Mortgage servicing rights	0	0
LIABILITIES
Deposits	5,916,154	5,940,117
Collateral payable	52,516	50,920
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—commercial loans
ASSETS
Derivative financial assets		0
Fair Value Measurements \| Level 1 \| Interest rate swap contracts - cash flow hedge
LIABILITIES
Derivative financial liabilities	0	0
Fair Value Measurements \| Level 2
ASSETS
Cash and due from banks, including interest-bearing deposits	0	0
Securities available for sale	893,647	835,595
Loans held for sale		153
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	1,862,586	1,571,481
Collateral payable	0	0
Short-term borrowings	150,000	415,000
Long-term borrowings	50,652	38,995
Junior subordinated debt securities	49,418	49,358
Fair Value Measurements \| Level 2 \| Interest rate swap contracts - commercial loans
ASSETS
Derivative financial assets	60,890
LIABILITIES
Derivative financial liabilities	61,271	63,554
Fair Value Measurements \| Level 2 \| Interest rate swap contracts—commercial loans
ASSETS
Derivative financial assets		63,018
Fair Value Measurements \| Level 2 \| Interest rate swap contracts - cash flow hedge
LIABILITIES
Derivative financial liabilities	9,589	14,739
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		0
Portfolio loans, net	7,362,898	7,263,270
Collateral receivable	0	0
Securities held in a deferred compensation plan	0	0
Mortgage servicing rights	8,533	8,704
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—commercial loans
ASSETS
Derivative financial assets		0
Fair Value Measurements \| Level 3 \| Interest rate swap contracts - cash flow hedge
LIABILITIES
Derivative financial liabilities	$ 0	$ 0

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