Fair Value Measurements - Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
ASSETS
Available-for-sale debt securities	$ 1,067,492	$ 909,651
Marketable equity securities	1,084	1,142
U.S. Treasury securities
ASSETS
Available-for-sale debt securities	136,282	95,327
Obligations of U.S. government corporations and agencies
ASSETS
Available-for-sale debt securities	52,815	70,348
Collateralized mortgage obligations of U.S. government corporations and agencies
ASSETS
Available-for-sale debt securities	427,635	270,294
Residential mortgage-backed securities of U.S. government corporations and agencies
ASSETS
Available-for-sale debt securities	46,416	56,793
Commercial mortgage-backed securities of U.S. government corporations and agencies
ASSETS
Available-for-sale debt securities	333,994	341,300
Obligations of states and political subdivisions
ASSETS
Available-for-sale debt securities	69,850	75,089
Fair Value Measurements, Recurring
ASSETS
Available-for-sale debt securities	1,067,492	909,651
Marketable equity securities	1,084	1,142
Total Securities	1,068,576	910,793
Securities held in a deferred compensation plan	7,678	10,230
Total Assets	1,127,775	954,956
LIABILITIES
Total Liabilities	57,141	33,631
Fair Value Measurements, Recurring \| U.S. Treasury securities
ASSETS
Available-for-sale debt securities	136,282	95,327
Fair Value Measurements, Recurring \| Obligations of U.S. government corporations and agencies
ASSETS
Available-for-sale debt securities	52,815	70,348
Fair Value Measurements, Recurring \| Collateralized mortgage obligations of U.S. government corporations and agencies
ASSETS
Available-for-sale debt securities	427,635	270,294
Fair Value Measurements, Recurring \| Residential mortgage-backed securities of U.S. government corporations and agencies
ASSETS
Available-for-sale debt securities	46,416	56,793
Fair Value Measurements, Recurring \| Commercial mortgage-backed securities of U.S. government corporations and agencies
ASSETS
Available-for-sale debt securities	333,994	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	69,850	75,089
Fair Value Measurements, Recurring \| Interest rate swaps - commercial loans
ASSETS
Derivative financial assets	51,097	33,528
LIABILITIES
Derivative financial liabilities	51,193	33,631
Fair Value Measurements, Recurring \| Interest rate lock commitments
ASSETS
Derivative financial assets	56	401
Fair Value Measurements, Recurring \| Forward sale contracts - mortgage loans
ASSETS
Derivative financial assets		4
LIABILITIES
Derivative financial liabilities	2
Fair Value Measurements, Recurring \| Interest rate swaps - cash flow hedge
ASSETS
Derivative financial assets	368	0
LIABILITIES
Derivative financial liabilities	5,946
Fair Value Measurements, Recurring \| Level 1
ASSETS
Available-for-sale debt securities	136,282	95,327
Marketable equity securities	1,015	1,061
Total Securities	137,297	96,388
Securities held in a deferred compensation plan	7,678	10,230
Total Assets	144,975	106,618
LIABILITIES
Total Liabilities	0	0
Fair Value Measurements, Recurring \| Level 1 \| U.S. Treasury securities
ASSETS
Available-for-sale debt securities	136,282	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 \| Interest rate lock commitments
ASSETS
Derivative financial assets	0	0
Fair Value Measurements, Recurring \| Level 1 \| Forward sale contracts - mortgage loans
ASSETS
Derivative financial assets		0
LIABILITIES
Derivative financial liabilities	0
Fair Value Measurements, Recurring \| Level 1 \| Interest rate swaps - cash flow hedge
ASSETS
Derivative financial assets	0	0
LIABILITIES
Derivative financial liabilities	0
Fair Value Measurements, Recurring \| Level 2
ASSETS
Available-for-sale debt securities	931,210	814,324
Marketable equity securities	69	81
Total Securities	931,279	814,405
Securities held in a deferred compensation plan	0	0
Total Assets	982,744	847,933
LIABILITIES
Total Liabilities	57,139	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	52,815	70,348
Fair Value Measurements, Recurring \| Level 2 \| Collateralized mortgage obligations of U.S. government corporations and agencies
ASSETS
Available-for-sale debt securities	427,635	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	46,416	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	333,994	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	69,850	75,089
Fair Value Measurements, Recurring \| Level 2 \| Interest rate swaps - commercial loans
ASSETS
Derivative financial assets	51,097	33,528
LIABILITIES
Derivative financial liabilities	51,193	33,631
Fair Value Measurements, Recurring \| Level 2 \| Interest rate lock commitments
ASSETS
Derivative financial assets	0	0
Fair Value Measurements, Recurring \| Level 2 \| Forward sale contracts - mortgage loans
ASSETS
Derivative financial assets		0
LIABILITIES
Derivative financial liabilities	0
Fair Value Measurements, Recurring \| Level 2 \| Interest rate swaps - cash flow hedge
ASSETS
Derivative financial assets	368	0
LIABILITIES
Derivative financial liabilities	5,946
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	56	405
LIABILITIES
Total Liabilities	2	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 \| Interest rate lock commitments
ASSETS
Derivative financial assets	56	401
Fair Value Measurements, Recurring \| Level 3 \| Forward sale contracts - mortgage loans
ASSETS
Derivative financial assets		4
LIABILITIES
Derivative financial liabilities	2
Fair Value Measurements, Recurring \| Level 3 \| Interest rate swaps - cash flow hedge
ASSETS
Derivative financial assets	0	$ 0
LIABILITIES
Derivative financial liabilities	$ 0

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