Fair Value Measurements - Carrying Values and Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
ASSETS
Securities available for sale	$ 970,728	$ 970,391
Portfolio loans, net	7,551,232	7,545,375
Derivative financial assets	72,093	63,018
LIABILITIES
Junior subordinated debt securities	49,373	49,358
Derivative financial liabilities	90,982	78,293
Carrying Value
ASSETS
Cash and due from banks, including interest-bearing deposits	207,462	233,612
Securities available for sale	970,728	970,391
Loans held for sale		153
Portfolio loans, net	7,551,232	7,545,375
Collateral receivable	6,770	5,356
Securities held in a deferred compensation plan	10,257	9,399
Mortgage servicing rights	6,153	6,345
LIABILITIES
Deposits	7,600,347	7,521,769
Collateral payable	58,587	50,920
Short-term borrowings	285,000	415,000
Long-term borrowings	39,156	39,277
Junior subordinated debt securities	49,373	49,358
Carrying Value | Interest rate swaps - commercial loans
ASSETS
Derivative financial assets	72,093
LIABILITIES
Derivative financial liabilities	72,578	63,554
Carrying Value | Interest rate swap contracts—commercial loans
ASSETS
Derivative financial assets		63,018
Carrying Value | Interest rate swaps - cash flow hedge
LIABILITIES
Derivative financial liabilities	18,404	14,739
Fair Value Measurements
ASSETS
Cash and due from banks, including interest-bearing deposits	207,462	233,612
Securities available for sale	970,728	970,391
Loans held for sale		153
Portfolio loans, net	7,247,276	7,263,270
Collateral receivable	6,770	5,356
Securities held in a deferred compensation plan	10,257	9,399
Mortgage servicing rights	8,809	8,704
LIABILITIES
Deposits	7,588,523	7,511,598
Collateral payable	58,587	50,920
Short-term borrowings	284,631	415,000
Long-term borrowings	38,924	38,995
Junior subordinated debt securities	49,373	49,358
Fair Value Measurements | Interest rate swaps - commercial loans
ASSETS
Derivative financial assets	72,093
LIABILITIES
Derivative financial liabilities	72,578	63,554
Fair Value Measurements | Interest rate swap contracts—commercial loans
ASSETS
Derivative financial assets		63,018
Fair Value Measurements | Interest rate swaps - cash flow hedge
LIABILITIES
Derivative financial liabilities	18,404	14,739
Fair Value Measurements | Level 1
ASSETS
Cash and due from banks, including interest-bearing deposits	207,462	233,612
Securities available for sale	133,521	134,796
Loans held for sale		0
Portfolio loans, net	0	0
Collateral receivable	6,770	5,356
Securities held in a deferred compensation plan	10,257	9,399
Mortgage servicing rights	0	0
LIABILITIES
Deposits	5,855,869	5,940,117
Collateral payable	58,587	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 swaps - 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 swaps - 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	837,207	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	1,732,654	1,571,481
Collateral payable	0	0
Short-term borrowings	284,631	415,000
Long-term borrowings	38,924	38,995
Junior subordinated debt securities	49,373	49,358
Fair Value Measurements | Level 2 | Interest rate swaps - commercial loans
ASSETS
Derivative financial assets	72,093
LIABILITIES
Derivative financial liabilities	72,578	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 swaps - cash flow hedge
LIABILITIES
Derivative financial liabilities	18,404	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	7,247,276	7,263,270
Collateral receivable	0	0
Securities held in a deferred compensation plan	0	0
Mortgage servicing rights	8,809	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 swaps - 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 swaps - cash flow hedge
LIABILITIES
Derivative financial liabilities	$ 0	$ 0