Fair Value Measurements - Carrying Values and Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
ASSETS
Securities available for sale	$ 977,958	$ 970,391
Portfolio loans, net	7,607,420	7,545,375
Derivative financial assets	70,313	63,018
LIABILITIES
Junior subordinated debt securities	49,388	49,358
Derivative financial liabilities	87,921	78,293
Carrying Value
ASSETS
Cash and due from banks, including interest-bearing deposits	246,310	233,612
Securities available for sale	977,958	970,391
Loans held for sale	188	153
Portfolio loans, net	7,607,420	7,545,375
Collateral receivable	6,265	5,356
Securities held in a deferred compensation plan	10,503	9,399
Mortgage servicing rights	5,972	6,345
LIABILITIES
Deposits	7,680,336	7,521,769
Collateral payable	56,680	50,920
Short-term borrowings	275,000	415,000
Long-term borrowings	39,034	39,277
Junior subordinated debt securities	49,388	49,358
Carrying Value | Interest rate swaps - commercial loans
ASSETS
Derivative financial assets	70,313
LIABILITIES
Derivative financial liabilities	70,765	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	17,156	14,739
Fair Value Measurements
ASSETS
Cash and due from banks, including interest-bearing deposits	246,310	233,612
Securities available for sale	977,958	970,391
Loans held for sale	188	153
Portfolio loans, net	7,306,637	7,263,270
Collateral receivable	6,265	5,356
Securities held in a deferred compensation plan	10,503	9,399
Mortgage servicing rights	8,664	8,704
LIABILITIES
Deposits	7,669,604	7,511,598
Collateral payable	56,680	50,920
Short-term borrowings	274,593	415,000
Long-term borrowings	38,881	38,995
Junior subordinated debt securities	49,388	49,358
Fair Value Measurements | Interest rate swaps - commercial loans
ASSETS
Derivative financial assets	70,313
LIABILITIES
Derivative financial liabilities	70,765	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	17,156	14,739
Fair Value Measurements | Level 1
ASSETS
Cash and due from banks, including interest-bearing deposits	246,310	233,612
Securities available for sale	117,568	134,796
Loans held for sale	0	0
Portfolio loans, net	0	0
Collateral receivable	6,265	5,356
Securities held in a deferred compensation plan	10,503	9,399
Mortgage servicing rights	0	0
LIABILITIES
Deposits	5,911,186	5,940,117
Collateral payable	56,680	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	860,390	835,595
Loans held for sale	188	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	1,758,418	1,571,481
Collateral payable	0	0
Short-term borrowings	274,593	415,000
Long-term borrowings	38,881	38,995
Junior subordinated debt securities	49,388	49,358
Fair Value Measurements | Level 2 | Interest rate swaps - commercial loans
ASSETS
Derivative financial assets	70,313
LIABILITIES
Derivative financial liabilities	70,765	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	17,156	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	0
Portfolio loans, net	7,306,637	7,263,270
Collateral receivable	0	0
Securities held in a deferred compensation plan	0	0
Mortgage servicing rights	8,664	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