Fair Value Measurements - Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
ASSETS
Debt securities	$ 954,267	$ 1,001,784
Equity securities	995	994
Derivative financial assets	93,601	83,456
LIABILITIES
Derivative financial liabilities	120,106	104,817
U.S. Treasury securities
ASSETS
Debt securities	130,037	131,695
Obligations of U.S. government corporations and agencies
ASSETS
Debt securities	42,049	41,811
Collateralized mortgage obligations of U.S. government corporations and agencies
ASSETS
Debt securities	429,978	428,407
Residential mortgage-backed securities of U.S. government corporations and agencies
ASSETS
Debt securities	36,886	41,587
Commercial mortgage-backed securities of U.S. government corporations and agencies
ASSETS
Debt securities	286,107	327,313
Obligations of states and political subdivisions
ASSETS
Debt securities	29,210	30,471
Fair Value Measurements, Recurring
ASSETS
Debt securities	954,267	1,001,784
Equity securities	995	994
Total Securities Available for Sale	955,262	1,002,778
Securities held in a deferred compensation plan	8,289	8,087
Total Assets	1,057,152	1,094,321
LIABILITIES
Total Liabilities	120,106	104,817
Fair Value Measurements, Recurring \| U.S. Treasury securities
ASSETS
Debt securities	130,037	131,695
Fair Value Measurements, Recurring \| Obligations of U.S. government corporations and agencies
ASSETS
Debt securities	42,049	41,811
Fair Value Measurements, Recurring \| Collateralized mortgage obligations of U.S. government corporations and agencies
ASSETS
Debt securities	429,978	428,407
Fair Value Measurements, Recurring \| Residential mortgage-backed securities of U.S. government corporations and agencies
ASSETS
Debt securities	36,886	41,587
Fair Value Measurements, Recurring \| Commercial mortgage-backed securities of U.S. government corporations and agencies
ASSETS
Debt securities	286,107	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	29,210	30,471
Fair Value Measurements, Recurring \| Interest rate swaps - commercial loans
ASSETS
Derivative financial assets	93,601	83,449
LIABILITIES
Derivative financial liabilities	94,438	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	25,668	21,368
Fair Value Measurements, Recurring \| Level 1
ASSETS
Debt securities	130,037	131,695
Equity securities	923	952
Total Securities Available for Sale	130,960	132,647
Securities held in a deferred compensation plan	8,289	8,087
Total Assets	139,249	140,734
LIABILITIES
Total Liabilities	0	0
Fair Value Measurements, Recurring \| Level 1 \| U.S. Treasury securities
ASSETS
Debt securities	130,037	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	824,230	870,089
Equity securities	72	42
Total Securities Available for Sale	824,302	870,131
Securities held in a deferred compensation plan	0	0
Total Assets	917,903	953,580
LIABILITIES
Total Liabilities	120,106	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	42,049	41,811
Fair Value Measurements, Recurring \| Level 2 \| Collateralized mortgage obligations of U.S. government corporations and agencies
ASSETS
Debt securities	429,978	428,407
Fair Value Measurements, Recurring \| Level 2 \| Residential mortgage-backed securities of U.S. government corporations and agencies
ASSETS
Debt securities	36,886	41,587
Fair Value Measurements, Recurring \| Level 2 \| Commercial mortgage-backed securities of U.S. government corporations and agencies
ASSETS
Debt securities	286,107	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	29,210	30,471
Fair Value Measurements, Recurring \| Level 2 \| Interest rate swaps - commercial loans
ASSETS
Derivative financial assets	93,601	83,449
LIABILITIES
Derivative financial liabilities	94,438	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	25,668	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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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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