Fair Value Measurements - Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
ASSETS
Available-for-sale debt securities	$ 996,403	$ 909,651
Marketable equity securities	1,025	1,142
Derivative financial assets	88,896	33,933
LIABILITIES
Derivative financial liabilities	111,647	33,631
U.S. Treasury securities
ASSETS
Available-for-sale debt securities	120,825	95,327
Obligations of U.S. government corporations and agencies
ASSETS
Available-for-sale debt securities	51,784	70,348
Collateralized mortgage obligations of U.S. government corporations and agencies
ASSETS
Available-for-sale debt securities	419,719	270,294
Residential mortgage-backed securities of U.S. government corporations and agencies
ASSETS
Available-for-sale debt securities	41,984	56,793
Commercial mortgage-backed securities of U.S. government corporations and agencies
ASSETS
Available-for-sale debt securities	323,469	341,300
Obligations of states and political subdivisions
ASSETS
Available-for-sale debt securities	38,122	75,089
Fair Value Measurements, Recurring
ASSETS
Available-for-sale debt securities	996,403	909,651
Marketable equity securities	1,025	1,142
Total Securities	997,428	910,793
Securities held in a deferred compensation plan	7,354	10,230
Total Assets	1,093,678	954,956
LIABILITIES
Total Liabilities	111,647	33,631
Fair Value Measurements, Recurring \| U.S. Treasury securities
ASSETS
Available-for-sale debt securities	120,825	95,327
Fair Value Measurements, Recurring \| Obligations of U.S. government corporations and agencies
ASSETS
Available-for-sale debt securities	51,784	70,348
Fair Value Measurements, Recurring \| Collateralized mortgage obligations of U.S. government corporations and agencies
ASSETS
Available-for-sale debt securities	419,719	270,294
Fair Value Measurements, Recurring \| Residential mortgage-backed securities of U.S. government corporations and agencies
ASSETS
Available-for-sale debt securities	41,984	56,793
Fair Value Measurements, Recurring \| Commercial mortgage-backed securities of U.S. government corporations and agencies
ASSETS
Available-for-sale debt securities	323,469	341,300
Fair Value Measurements, Recurring \| Corporate obligations
ASSETS
Available-for-sale debt securities	500	500
Fair Value Measurements, Recurring \| Obligations of states and political subdivisions
ASSETS
Available-for-sale debt securities	38,122	75,089
Fair Value Measurements, Recurring \| Interest rate swaps - commercial loans
ASSETS
Derivative financial assets	88,888	33,528
LIABILITIES
Derivative financial liabilities	88,920	33,631
Fair Value Measurements, Recurring \| Forward sale contracts - mortgage loans
ASSETS
Derivative financial assets	8	4
Fair Value Measurements, Recurring \| Interest rate lock commitments
ASSETS
Derivative financial assets		401
LIABILITIES
Derivative financial liabilities	3
Fair Value Measurements, Recurring \| Interest rate swaps - cash flow hedge
LIABILITIES
Derivative financial liabilities	22,724
Fair Value Measurements, Recurring \| Level 1
ASSETS
Available-for-sale debt securities	120,825	95,327
Marketable equity securities	963	1,061
Total Securities	121,788	96,388
Securities held in a deferred compensation plan	7,354	10,230
Total Assets	129,142	106,618
LIABILITIES
Total Liabilities	0	0
Fair Value Measurements, Recurring \| Level 1 \| U.S. Treasury securities
ASSETS
Available-for-sale debt securities	120,825	95,327
Fair Value Measurements, Recurring \| Level 1 \| Obligations of U.S. government corporations and agencies
ASSETS
Available-for-sale debt securities	0	0
Fair Value Measurements, Recurring \| Level 1 \| Collateralized mortgage obligations of U.S. government corporations and agencies
ASSETS
Available-for-sale debt securities	0	0
Fair Value Measurements, Recurring \| Level 1 \| Residential mortgage-backed securities of U.S. government corporations and agencies
ASSETS
Available-for-sale debt securities	0	0
Fair Value Measurements, Recurring \| Level 1 \| Commercial mortgage-backed securities of U.S. government corporations and agencies
ASSETS
Available-for-sale debt securities	0	0
Fair Value Measurements, Recurring \| Level 1 \| Corporate obligations
ASSETS
Available-for-sale debt securities	0	0
Fair Value Measurements, Recurring \| Level 1 \| Obligations of states and political subdivisions
ASSETS
Available-for-sale 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 \| Forward sale contracts - mortgage loans
ASSETS
Derivative financial assets	0	0
Fair Value Measurements, Recurring \| Level 1 \| Interest rate lock commitments
ASSETS
Derivative financial assets		0
LIABILITIES
Derivative financial liabilities	0
Fair Value Measurements, Recurring \| Level 1 \| Interest rate swaps - cash flow hedge
LIABILITIES
Derivative financial liabilities	0
Fair Value Measurements, Recurring \| Level 2
ASSETS
Available-for-sale debt securities	875,578	814,324
Marketable equity securities	62	81
Total Securities	875,640	814,405
Securities held in a deferred compensation plan	0	0
Total Assets	964,528	847,933
LIABILITIES
Total Liabilities	111,644	33,631
Fair Value Measurements, Recurring \| Level 2 \| U.S. Treasury securities
ASSETS
Available-for-sale debt securities	0	0
Fair Value Measurements, Recurring \| Level 2 \| Obligations of U.S. government corporations and agencies
ASSETS
Available-for-sale debt securities	51,784	70,348
Fair Value Measurements, Recurring \| Level 2 \| Collateralized mortgage obligations of U.S. government corporations and agencies
ASSETS
Available-for-sale debt securities	419,719	270,294
Fair Value Measurements, Recurring \| Level 2 \| Residential mortgage-backed securities of U.S. government corporations and agencies
ASSETS
Available-for-sale debt securities	41,984	56,793
Fair Value Measurements, Recurring \| Level 2 \| Commercial mortgage-backed securities of U.S. government corporations and agencies
ASSETS
Available-for-sale debt securities	323,469	341,300
Fair Value Measurements, Recurring \| Level 2 \| Corporate obligations
ASSETS
Available-for-sale debt securities	500	500
Fair Value Measurements, Recurring \| Level 2 \| Obligations of states and political subdivisions
ASSETS
Available-for-sale debt securities	38,122	75,089
Fair Value Measurements, Recurring \| Level 2 \| Interest rate swaps - commercial loans
ASSETS
Derivative financial assets	88,888	33,528
LIABILITIES
Derivative financial liabilities	88,920	33,631
Fair Value Measurements, Recurring \| Level 2 \| Forward sale contracts - mortgage loans
ASSETS
Derivative financial assets	0	0
Fair Value Measurements, Recurring \| Level 2 \| Interest rate lock commitments
ASSETS
Derivative financial assets		0
LIABILITIES
Derivative financial liabilities	0
Fair Value Measurements, Recurring \| Level 2 \| Interest rate swaps - cash flow hedge
LIABILITIES
Derivative financial liabilities	22,724
Fair Value Measurements, Recurring \| Level 3
ASSETS
Available-for-sale debt securities	0	0
Marketable equity securities	0	0
Total Securities	0	0
Securities held in a deferred compensation plan	0	0
Total Assets	8	405
LIABILITIES
Total Liabilities	3	0
Fair Value Measurements, Recurring \| Level 3 \| U.S. Treasury securities
ASSETS
Available-for-sale debt securities	0	0
Fair Value Measurements, Recurring \| Level 3 \| Obligations of U.S. government corporations and agencies
ASSETS
Available-for-sale debt securities	0	0
Fair Value Measurements, Recurring \| Level 3 \| Collateralized mortgage obligations of U.S. government corporations and agencies
ASSETS
Available-for-sale debt securities	0	0
Fair Value Measurements, Recurring \| Level 3 \| Residential mortgage-backed securities of U.S. government corporations and agencies
ASSETS
Available-for-sale debt securities	0	0
Fair Value Measurements, Recurring \| Level 3 \| Commercial mortgage-backed securities of U.S. government corporations and agencies
ASSETS
Available-for-sale debt securities	0	0
Fair Value Measurements, Recurring \| Level 3 \| Corporate obligations
ASSETS
Available-for-sale debt securities	0	0
Fair Value Measurements, Recurring \| Level 3 \| Obligations of states and political subdivisions
ASSETS
Available-for-sale 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 \| Forward sale contracts - mortgage loans
ASSETS
Derivative financial assets	8	4
Fair Value Measurements, Recurring \| Level 3 \| Interest rate lock commitments
ASSETS
Derivative financial assets		$ 401
LIABILITIES
Derivative financial liabilities	3
Fair Value Measurements, Recurring \| Level 3 \| Interest rate swaps - cash flow hedge
LIABILITIES
Derivative financial liabilities	$ 0

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