Fair Value Measurements - Carrying Values and Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
ASSETS
Securities available for sale	$ 1,009,518	$ 987,659
Portfolio loans, net	7,866,111	7,978,779
Derivative financial assets	32,977	33,750
LIABILITIES
Junior subordinated debt securities	49,493	49,478
Derivative financial liabilities	35,068	36,014
Interest rate swaps - commercial loans
ASSETS
Derivative financial assets	32,943	33,669
LIABILITIES
Derivative financial liabilities	35,068	36,014
Carrying Value
ASSETS
Cash and due from banks, including interest-bearing deposits	339,059	163,436
Securities available for sale	1,009,518	987,659
Loans held for sale	694	1,010
Portfolio loans, net	7,866,111	7,978,779
Collateral receivable		2
Securities held in a deferred compensation plan	9,453	14,212
Mortgage servicing rights	4,958	5,034
LIABILITIES
Deposits	8,185,219	7,958,831
Collateral payable	31,087	26,964
Short-term borrowings	50,000	165,000
Long-term borrowings	50,794	50,815
Junior subordinated debt securities	49,493	49,478
Carrying Value \| Interest rate lock commitments - mortgage loans
ASSETS
Derivative financial assets		81
Carrying Value \| Interest rate swaps - commercial loans
ASSETS
Derivative financial assets		33,669
Carrying Value \| Interest rate lock commitments - mortgage loans
ASSETS
Derivative financial assets	34
Carrying Value \| Interest rate swap contracts - commercial loans
ASSETS
Derivative financial assets	32,943
LIABILITIES
Derivative financial liabilities	33,200	33,990
Carrying Value \| Interest rate swap contracts - cash flow hedge
LIABILITIES
Derivative financial liabilities	1,868	2,024
Fair Value Measurements
ASSETS
Cash and due from banks, including interest-bearing deposits	339,059	163,436
Securities available for sale	1,009,518	987,659
Loans held for sale	694	1,010
Portfolio loans, net	7,687,285	7,807,824
Collateral receivable		2
Securities held in a deferred compensation plan	9,453	14,212
Mortgage servicing rights	8,033	8,034
LIABILITIES
Deposits	8,180,325	7,956,632
Collateral payable	31,087	26,964
Short-term borrowings	50,000	165,000
Long-term borrowings	50,793	50,856
Junior subordinated debt securities	49,493	49,478
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		33,669
Fair Value Measurements \| Interest rate lock commitments - mortgage loans
ASSETS
Derivative financial assets	34
Fair Value Measurements \| Interest rate swap contracts - commercial loans
ASSETS
Derivative financial assets	32,943
LIABILITIES
Derivative financial liabilities	33,200	33,990
Fair Value Measurements \| Interest rate swap contracts - cash flow hedge
LIABILITIES
Derivative financial liabilities	1,868	2,024
Fair Value Measurements \| Level 1
ASSETS
Cash and due from banks, including interest-bearing deposits	339,059	163,436
Securities available for sale	85,539	85,889
Loans held for sale	0	0
Portfolio loans, net	0	0
Collateral receivable		2
Securities held in a deferred compensation plan	9,453	14,212
Mortgage servicing rights	0	0
LIABILITIES
Deposits	6,205,727	6,010,039
Collateral payable	31,087	26,964
Short-term borrowings	0	0
Long-term borrowings	0	0
Junior subordinated debt securities	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 1 \| Interest rate lock commitments - mortgage 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 2
ASSETS
Cash and due from banks, including interest-bearing deposits	0	0
Securities available for sale	923,979	901,770
Loans held for sale	694	1,010
Portfolio loans, net	0	0
Collateral receivable		0
Securities held in a deferred compensation plan	0	0
Mortgage servicing rights	0	0
LIABILITIES
Deposits	1,974,598	1,946,593
Collateral payable	0	0
Short-term borrowings	50,000	165,000
Long-term borrowings	50,793	50,856
Junior subordinated debt securities	49,493	49,478
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		33,669
Fair Value Measurements \| Level 2 \| Interest rate lock commitments - mortgage loans
ASSETS
Derivative financial assets	0
Fair Value Measurements \| Level 2 \| Interest rate swap contracts - commercial loans
ASSETS
Derivative financial assets	32,943
LIABILITIES
Derivative financial liabilities	33,200	33,990
Fair Value Measurements \| Level 2 \| Interest rate swap contracts - cash flow hedge
LIABILITIES
Derivative financial liabilities	1,868	2,024
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	7,687,285	7,807,824
Collateral receivable		0
Securities held in a deferred compensation plan	0	0
Mortgage servicing rights	8,033	8,034
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 lock commitments - mortgage loans
ASSETS
Derivative financial assets		81
Fair Value Measurements \| Level 3 \| Interest rate swaps - commercial loans
ASSETS
Derivative financial assets		0
Fair Value Measurements \| Level 3 \| Interest rate lock commitments - mortgage loans
ASSETS
Derivative financial assets	34
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

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