Fair Value Measurements - Carrying Values and Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
ASSETS
Securities	$ 1,028,218	$ 910,793
Portfolio loans, net	6,863,996	6,901,414
LIABILITIES
Junior subordinated debt securities	54,408	54,393
Carrying Value
ASSETS
Cash and due from banks, including interest-bearing deposits	823,757	922,215
Securities	1,028,218	910,793
Loans held for sale	1,346	1,522
Portfolio loans, net	6,863,996	6,901,414
Collateral receivable	0	37,363
Securities held in a deferred compensation plan	8,888	10,230
Mortgage servicing rights	7,789	7,677
LIABILITIES
Deposits	7,960,458	7,996,524
Collateral payable	23,501
Securities sold under repurchase agreements	70,112	84,491
Short-term borrowings		0
Long-term borrowings	22,172	22,430
Junior subordinated debt securities	54,408	54,393
Carrying Value \| Interest rate swaps - commercial loans
ASSETS
Derivative financial assets	29,056
LIABILITIES
Derivative financial liabilities	29,092
Carrying Value \| Interest rate swaps - cash flow hedge
ASSETS
Derivative financial assets	135
LIABILITIES
Derivative financial liabilities	2,600
Carrying Value \| Interest rate swaps - commercial loans
ASSETS
Derivative financial assets		33,528
LIABILITIES
Derivative financial liabilities		33,631
Carrying Value \| Interest rate lock commitments
ASSETS
Derivative financial assets	185	401
Carrying Value \| Forward sale contracts - mortgage loans
ASSETS
Derivative financial assets	192	4
Fair Value Measurements
ASSETS
Cash and due from banks, including interest-bearing deposits	823,757	922,215
Securities	1,028,218	910,793
Loans held for sale	1,346	1,522
Portfolio loans, net	6,671,212	6,815,468
Collateral receivable	0	37,363
Securities held in a deferred compensation plan	8,888	10,230
Mortgage servicing rights	9,791	7,677
LIABILITIES
Deposits	7,947,434	7,992,942
Collateral payable	23,501
Securities sold under repurchase agreements	70,112	84,491
Short-term borrowings		0
Long-term borrowings	21,954	22,678
Junior subordinated debt securities	54,408	54,393
Fair Value Measurements \| Interest rate swaps - commercial loans
ASSETS
Derivative financial assets	29,056
LIABILITIES
Derivative financial liabilities	29,092
Fair Value Measurements \| Interest rate swaps - cash flow hedge
ASSETS
Derivative financial assets	135
LIABILITIES
Derivative financial liabilities	2,600
Fair Value Measurements \| Interest rate swaps - commercial loans
ASSETS
Derivative financial assets		33,528
LIABILITIES
Derivative financial liabilities		33,631
Fair Value Measurements \| Interest rate lock commitments
ASSETS
Derivative financial assets	185	401
Fair Value Measurements \| Forward sale contracts - mortgage loans
ASSETS
Derivative financial assets	192	4
Fair Value Measurements \| Level 1
ASSETS
Cash and due from banks, including interest-bearing deposits	823,757	922,215
Securities	131,054	96,388
Loans held for sale	0	0
Portfolio loans, net	0	0
Collateral receivable	0	37,363
Securities held in a deferred compensation plan	8,888	10,230
Mortgage servicing rights	0	0
LIABILITIES
Deposits	6,921,872	6,908,453
Collateral payable	23,501
Securities sold under repurchase agreements	70,112	84,491
Short-term borrowings		0
Long-term borrowings	4,249	4,300
Junior subordinated debt securities	54,408	54,393
Fair Value Measurements \| Level 1 \| Interest rate swaps - commercial loans
ASSETS
Derivative financial assets	0
LIABILITIES
Derivative financial liabilities	0
Fair Value Measurements \| Level 1 \| Interest rate swaps - cash flow hedge
ASSETS
Derivative financial assets	0
LIABILITIES
Derivative financial liabilities	0
Fair Value Measurements \| Level 1 \| Interest rate swaps - commercial loans
ASSETS
Derivative financial assets		0
LIABILITIES
Derivative financial liabilities		0
Fair Value Measurements \| Level 1 \| Interest rate lock commitments
ASSETS
Derivative financial assets	0	0
Fair Value Measurements \| Level 1 \| Forward sale contracts - mortgage loans
ASSETS
Derivative financial assets	0	0
Fair Value Measurements \| Level 2
ASSETS
Cash and due from banks, including interest-bearing deposits	0	0
Securities	897,164	814,405
Loans held for sale	0	0
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	1,025,562	1,084,489
Collateral payable	0
Securities sold under repurchase agreements	0	0
Short-term borrowings		0
Long-term borrowings	17,705	18,378
Junior subordinated debt securities	0	0
Fair Value Measurements \| Level 2 \| Interest rate swaps - commercial loans
ASSETS
Derivative financial assets	29,056
LIABILITIES
Derivative financial liabilities	29,092
Fair Value Measurements \| Level 2 \| Interest rate swaps - cash flow hedge
ASSETS
Derivative financial assets	135
LIABILITIES
Derivative financial liabilities	2,600
Fair Value Measurements \| Level 2 \| Interest rate swaps - commercial loans
ASSETS
Derivative financial assets		33,528
LIABILITIES
Derivative financial liabilities		33,631
Fair Value Measurements \| Level 2 \| Interest rate lock commitments
ASSETS
Derivative financial assets	0	0
Fair Value Measurements \| Level 2 \| Forward sale contracts - mortgage loans
ASSETS
Derivative financial assets	0	0
Fair Value Measurements \| Level 3
ASSETS
Cash and due from banks, including interest-bearing deposits	0	0
Securities	0	0
Loans held for sale	1,346	1,522
Portfolio loans, net	6,671,212	6,815,468
Collateral receivable	0	0
Securities held in a deferred compensation plan	0	0
Mortgage servicing rights	9,791	7,677
LIABILITIES
Deposits	0	0
Collateral payable	0
Securities sold under repurchase agreements	0	0
Short-term borrowings		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
Fair Value Measurements \| Level 3 \| Interest rate swaps - cash flow hedge
ASSETS
Derivative financial assets	0
LIABILITIES
Derivative financial liabilities	0
Fair Value Measurements \| Level 3 \| Interest rate swaps - commercial loans
ASSETS
Derivative financial assets		0
LIABILITIES
Derivative financial liabilities		0
Fair Value Measurements \| Level 3 \| Interest rate lock commitments
ASSETS
Derivative financial assets	185	401
Fair Value Measurements \| Level 3 \| Forward sale contracts - mortgage loans
ASSETS
Derivative financial assets	$ 192	$ 4

Debt Securities, Available-for-sale and Equity Securities, FV-NI

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Securities Payable As Collateral, Fair Value Disclosure

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits.

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Amount excluding accrued interest, after allowance for credit loss, of financing receivable.

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Carrying value as of the balance sheet date of long-term debt (with maturities initially due after one year or beyond the operating cycle if longer) identified as Junior Subordinated Notes, which have a lower priority than senior instruments, excluding current portion.

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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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Fair value portion of securities that an entity sells and agrees to repurchase at a specified date for a specified price.

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The carrying value as of the balance sheet date of the assets received as collateral against securities loaned to other broker-dealers. Borrowers of securities generally are required to provide collateral to the lenders of securities, commonly cash but sometimes other securities or standby letters of credit, with a value slightly higher than that of the securities borrowed. In instances where the entity is permitted to sell or re-pledge these securities, the entity reports the fair value of the collateral received and the related obligation to return the collateral as a liability.

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Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents the amount of short-term debt existing as of the balance sheet date.

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Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading) and investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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