Fair Value Measurements - Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
ASSETS
Debt securities	$ 969,425	$ 1,001,784
Equity securities	947	994
Derivative financial assets	81,968	83,456
LIABILITIES
Derivative financial liabilities	105,563	104,817
U.S. Treasury securities
ASSETS
Debt securities	131,235	131,695
Obligations of U.S. government corporations and agencies
ASSETS
Debt securities	41,865	41,811
Collateralized mortgage obligations of U.S. government corporations and agencies
ASSETS
Debt securities	428,889	428,407
Residential mortgage-backed securities of U.S. government corporations and agencies
ASSETS
Debt securities	39,780	41,587
Commercial mortgage-backed securities of U.S. government corporations and agencies
ASSETS
Debt securities	297,278	327,313
Obligations of states and political subdivisions
ASSETS
Debt securities	30,378	30,471
Fair Value Measurements, Recurring
ASSETS
Debt securities	969,425	1,001,784
Equity securities	947	994
Total Securities Available for Sale	970,372	1,002,778
Securities held in a deferred compensation plan	8,625	8,087
Total Assets	1,060,965	1,094,321
LIABILITIES
Total Liabilities	105,563	104,817
Fair Value Measurements, Recurring \| U.S. Treasury securities
ASSETS
Debt securities	131,235	131,695
Fair Value Measurements, Recurring \| Obligations of U.S. government corporations and agencies
ASSETS
Debt securities	41,865	41,811
Fair Value Measurements, Recurring \| Collateralized mortgage obligations of U.S. government corporations and agencies
ASSETS
Debt securities	428,889	428,407
Fair Value Measurements, Recurring \| Residential mortgage-backed securities of U.S. government corporations and agencies
ASSETS
Debt securities	39,780	41,587
Fair Value Measurements, Recurring \| Commercial mortgage-backed securities of U.S. government corporations and agencies
ASSETS
Debt securities	297,278	327,313
Fair Value Measurements, Recurring \| Corporate obligations
ASSETS
Debt securities		500
Fair Value Measurements, Recurring \| Obligations of states and political subdivisions
ASSETS
Debt securities	30,378	30,471
Fair Value Measurements, Recurring \| Interest rate swaps - commercial loans
ASSETS
Derivative financial assets	81,968	83,449
LIABILITIES
Derivative financial liabilities	81,968	83,449
Fair Value Measurements, Recurring \| Interest rate lock commitments
ASSETS
Derivative financial assets		5
Fair Value Measurements, Recurring \| Forward sale contracts—mortgage loans
ASSETS
Derivative financial assets		2
Fair Value Measurements, Recurring \| Interest rate swaps - cash flow hedge
LIABILITIES
Derivative financial liabilities	23,595	21,368
Fair Value Measurements, Recurring \| Level 1
ASSETS
Debt securities	131,235	131,695
Equity securities	899	952
Total Securities Available for Sale	132,134	132,647
Securities held in a deferred compensation plan	8,625	8,087
Total Assets	140,759	140,734
LIABILITIES
Total Liabilities	0	0
Fair Value Measurements, Recurring \| Level 1 \| U.S. Treasury securities
ASSETS
Debt securities	131,235	131,695
Fair Value Measurements, Recurring \| Level 1 \| Obligations of U.S. government corporations and agencies
ASSETS
Debt securities	0	0
Fair Value Measurements, Recurring \| Level 1 \| Collateralized mortgage obligations of U.S. government corporations and agencies
ASSETS
Debt securities	0	0
Fair Value Measurements, Recurring \| Level 1 \| Residential mortgage-backed securities of U.S. government corporations and agencies
ASSETS
Debt securities	0	0
Fair Value Measurements, Recurring \| Level 1 \| Commercial mortgage-backed securities of U.S. government corporations and agencies
ASSETS
Debt securities	0	0
Fair Value Measurements, Recurring \| Level 1 \| Corporate obligations
ASSETS
Debt securities		0
Fair Value Measurements, Recurring \| Level 1 \| Obligations of states and political subdivisions
ASSETS
Debt securities	0	0
Fair Value Measurements, Recurring \| Level 1 \| Interest rate swaps - commercial loans
ASSETS
Derivative financial assets	0	0
LIABILITIES
Derivative financial liabilities	0	0
Fair Value Measurements, Recurring \| Level 1 \| Interest rate lock commitments
ASSETS
Derivative financial assets		0
Fair Value Measurements, Recurring \| Level 1 \| Forward sale contracts—mortgage loans
ASSETS
Derivative financial assets		0
Fair Value Measurements, Recurring \| Level 1 \| Interest rate swaps - cash flow hedge
LIABILITIES
Derivative financial liabilities	0	0
Fair Value Measurements, Recurring \| Level 2
ASSETS
Debt securities	838,190	870,089
Equity securities	48	42
Total Securities Available for Sale	838,238	870,131
Securities held in a deferred compensation plan	0	0
Total Assets	920,206	953,580
LIABILITIES
Total Liabilities	105,563	104,817
Fair Value Measurements, Recurring \| Level 2 \| U.S. Treasury securities
ASSETS
Debt securities	0	0
Fair Value Measurements, Recurring \| Level 2 \| Obligations of U.S. government corporations and agencies
ASSETS
Debt securities	41,865	41,811
Fair Value Measurements, Recurring \| Level 2 \| Collateralized mortgage obligations of U.S. government corporations and agencies
ASSETS
Debt securities	428,889	428,407
Fair Value Measurements, Recurring \| Level 2 \| Residential mortgage-backed securities of U.S. government corporations and agencies
ASSETS
Debt securities	39,780	41,587
Fair Value Measurements, Recurring \| Level 2 \| Commercial mortgage-backed securities of U.S. government corporations and agencies
ASSETS
Debt securities	297,278	327,313
Fair Value Measurements, Recurring \| Level 2 \| Corporate obligations
ASSETS
Debt securities		500
Fair Value Measurements, Recurring \| Level 2 \| Obligations of states and political subdivisions
ASSETS
Debt securities	30,378	30,471
Fair Value Measurements, Recurring \| Level 2 \| Interest rate swaps - commercial loans
ASSETS
Derivative financial assets	81,968	83,449
LIABILITIES
Derivative financial liabilities	81,968	83,449
Fair Value Measurements, Recurring \| Level 2 \| Interest rate lock commitments
ASSETS
Derivative financial assets		0
Fair Value Measurements, Recurring \| Level 2 \| Forward sale contracts—mortgage loans
ASSETS
Derivative financial assets		0
Fair Value Measurements, Recurring \| Level 2 \| Interest rate swaps - cash flow hedge
LIABILITIES
Derivative financial liabilities	23,595	21,368
Fair Value Measurements, Recurring \| Level 3
ASSETS
Debt securities	0	0
Equity securities	0	0
Total Securities Available for Sale	0	0
Securities held in a deferred compensation plan	0	0
Total Assets	0	7
LIABILITIES
Total Liabilities	0	0
Fair Value Measurements, Recurring \| Level 3 \| U.S. Treasury securities
ASSETS
Debt securities	0	0
Fair Value Measurements, Recurring \| Level 3 \| Obligations of U.S. government corporations and agencies
ASSETS
Debt securities	0	0
Fair Value Measurements, Recurring \| Level 3 \| Collateralized mortgage obligations of U.S. government corporations and agencies
ASSETS
Debt securities	0	0
Fair Value Measurements, Recurring \| Level 3 \| Residential mortgage-backed securities of U.S. government corporations and agencies
ASSETS
Debt securities	0	0
Fair Value Measurements, Recurring \| Level 3 \| Commercial mortgage-backed securities of U.S. government corporations and agencies
ASSETS
Debt securities	0	0
Fair Value Measurements, Recurring \| Level 3 \| Corporate obligations
ASSETS
Debt securities		0
Fair Value Measurements, Recurring \| Level 3 \| Obligations of states and political subdivisions
ASSETS
Debt securities	0	0
Fair Value Measurements, Recurring \| Level 3 \| Interest rate swaps - commercial loans
ASSETS
Derivative financial assets	0	0
LIABILITIES
Derivative financial liabilities	0	0
Fair Value Measurements, Recurring \| Level 3 \| Interest rate lock commitments
ASSETS
Derivative financial assets		5
Fair Value Measurements, Recurring \| Level 3 \| Forward sale contracts—mortgage loans
ASSETS
Derivative financial assets		2
Fair Value Measurements, Recurring \| Level 3 \| Interest rate swaps - cash flow hedge
LIABILITIES
Derivative financial liabilities	$ 0	$ 0

Assets Held-in-Trust, Fair Value Disclosure

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount excluding accrued interest, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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