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Fair Value Measurements - Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
ASSETS |  |
Debt securities, available-for-sale | $ 770,393 | $ 779,133
Marketable equity securities | 3,300 | 5,150
U.S. Treasury securities |  |
ASSETS |  |
Debt securities, available-for-sale | 10,282 | 10,040
Obligations of U.S. government corporations and agencies |  |
ASSETS |  |
Debt securities, available-for-sale | 82,904 | 157,697
Collateralized mortgage obligations of U.S. government corporations and agencies |  |
ASSETS |  |
Debt securities, available-for-sale | 209,296 | 189,348
Residential mortgage-backed securities of U.S. government corporations and agencies |  |
ASSETS |  |
Debt securities, available-for-sale | 67,778 | 22,418
Commercial mortgage-backed securities of U.S. government corporations and agencies |  |
ASSETS |  |
Debt securities, available-for-sale | 273,681 | 275,870
Obligations of states and political subdivisions |  |
ASSETS |  |
Debt securities, available-for-sale | 124,427 | 116,133
Fair Value Measurements, Recurring |  |
ASSETS |  |
Debt securities, available-for-sale | 770,393 | 779,133
Marketable equity securities | 3,300 | 5,150
Total Securities | 773,693 | 784,283
Securities held in a deferred compensation plan | 6,794 | 5,987
Total Assets | 861,706 | 816,239
LIABILITIES |  |
Total Liabilities | 79,418 | 25,615
Fair Value Measurements, Recurring | U.S. Treasury securities |  |
ASSETS |  |
Debt securities, available-for-sale | 10,282 | 10,040
Fair Value Measurements, Recurring | Obligations of U.S. government corporations and agencies |  |
ASSETS |  |
Debt securities, available-for-sale | 82,904 | 157,697
Fair Value Measurements, Recurring | Collateralized mortgage obligations of U.S. government corporations and agencies |  |
ASSETS |  |
Debt securities, available-for-sale | 209,296 | 189,348
Fair Value Measurements, Recurring | Residential mortgage-backed securities of U.S. government corporations and agencies |  |
ASSETS |  |
Debt securities, available-for-sale | 67,778 | 22,418
Fair Value Measurements, Recurring | Commercial mortgage-backed securities of U.S. government corporations and agencies |  |
ASSETS |  |
Debt securities, available-for-sale | 273,681 | 275,870
Fair Value Measurements, Recurring | Corporate obligations |  |
ASSETS |  |
Debt securities, available-for-sale | 2,025 | 7,627
Fair Value Measurements, Recurring | Obligations of states and political subdivisions |  |
ASSETS |  |
Debt securities, available-for-sale | 124,427 | 116,133
Fair Value Measurements, Recurring | Interest rate swaps |  |
ASSETS |  |
Derivative financial assets | 78,319 | 25,647
LIABILITIES |  |
Derivative financial liabilities | 79,033 | 25,615
Fair Value Measurements, Recurring | Interest rate lock commitments |  |
ASSETS |  |
Derivative financial assets | 2,900 | 321
Fair Value Measurements, Recurring | Forward sale contracts |  |
ASSETS |  |
Derivative financial assets |  | 1
LIABILITIES |  |
Derivative financial liabilities | 385 |
Fair Value Measurements, Recurring | Level 1 |  |
ASSETS |  |
Debt securities, available-for-sale | 0 | 0
Marketable equity securities | 3,228 | 5,078
Total Securities | 3,228 | 5,078
Securities held in a deferred compensation plan | 6,794 | 5,987
Total Assets | 10,022 | 11,065
LIABILITIES |  |
Total Liabilities | 0 | 0
Fair Value Measurements, Recurring | Level 1 | U.S. Treasury securities |  |
ASSETS |  |
Debt securities, available-for-sale | 0 | 0
Fair Value Measurements, Recurring | Level 1 | Obligations of U.S. government corporations and agencies |  |
ASSETS |  |
Debt securities, available-for-sale | 0 | 0
Fair Value Measurements, Recurring | Level 1 | Collateralized mortgage obligations of U.S. government corporations and agencies |  |
ASSETS |  |
Debt securities, available-for-sale | 0 | 0
Fair Value Measurements, Recurring | Level 1 | Residential mortgage-backed securities of U.S. government corporations and agencies |  |
ASSETS |  |
Debt securities, available-for-sale | 0 | 0
Fair Value Measurements, Recurring | Level 1 | Commercial mortgage-backed securities of U.S. government corporations and agencies |  |
ASSETS |  |
Debt securities, available-for-sale | 0 | 0
Fair Value Measurements, Recurring | Level 1 | Corporate obligations |  |
ASSETS |  |
Debt securities, available-for-sale | 0 | 0
Fair Value Measurements, Recurring | Level 1 | Obligations of states and political subdivisions |  |
ASSETS |  |
Debt securities, available-for-sale | 0 | 0
Fair Value Measurements, Recurring | Level 1 | Interest rate swaps |  |
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 |  |
ASSETS |  |
Derivative financial assets |  | 0
LIABILITIES |  |
Derivative financial liabilities | 0 |
Fair Value Measurements, Recurring | Level 2 |  |
ASSETS |  |
Debt securities, available-for-sale | 770,393 | 779,133
Marketable equity securities | 72 | 72
Total Securities | 770,465 | 779,205
Securities held in a deferred compensation plan | 0 | 0
Total Assets | 848,784 | 805,174
LIABILITIES |  |
Total Liabilities | 79,418 | 25,615
Fair Value Measurements, Recurring | Level 2 | U.S. Treasury securities |  |
ASSETS |  |
Debt securities, available-for-sale | 10,282 | 10,040
Fair Value Measurements, Recurring | Level 2 | Obligations of U.S. government corporations and agencies |  |
ASSETS |  |
Debt securities, available-for-sale | 82,904 | 157,697
Fair Value Measurements, Recurring | Level 2 | Collateralized mortgage obligations of U.S. government corporations and agencies |  |
ASSETS |  |
Debt securities, available-for-sale | 209,296 | 189,348
Fair Value Measurements, Recurring | Level 2 | Residential mortgage-backed securities of U.S. government corporations and agencies |  |
ASSETS |  |
Debt securities, available-for-sale | 67,778 | 22,418
Fair Value Measurements, Recurring | Level 2 | Commercial mortgage-backed securities of U.S. government corporations and agencies |  |
ASSETS |  |
Debt securities, available-for-sale | 273,681 | 275,870
Fair Value Measurements, Recurring | Level 2 | Corporate obligations |  |
ASSETS |  |
Debt securities, available-for-sale | 2,025 | 7,627
Fair Value Measurements, Recurring | Level 2 | Obligations of states and political subdivisions |  |
ASSETS |  |
Debt securities, available-for-sale | 124,427 | 116,133
Fair Value Measurements, Recurring | Level 2 | Interest rate swaps |  |
ASSETS |  |
Derivative financial assets | 78,319 | 25,647
LIABILITIES |  |
Derivative financial liabilities | 79,033 | 25,615
Fair Value Measurements, Recurring | Level 2 | Interest rate lock commitments |  |
ASSETS |  |
Derivative financial assets | 0 | 321
Fair Value Measurements, Recurring | Level 2 | Forward sale contracts |  |
ASSETS |  |
Derivative financial assets |  | 1
LIABILITIES |  |
Derivative financial liabilities | 385 |
Fair Value Measurements, Recurring | Level 3 |  |
ASSETS |  |
Debt securities, available-for-sale | 0 | 0
Marketable equity securities | 0 | 0
Total Securities | 0 | 0
Securities held in a deferred compensation plan | 0 | 0
Total Assets | 2,900 | 0
LIABILITIES |  |
Total Liabilities | 0 | 0
Fair Value Measurements, Recurring | Level 3 | U.S. Treasury securities |  |
ASSETS |  |
Debt securities, available-for-sale | 0 | 0
Fair Value Measurements, Recurring | Level 3 | Obligations of U.S. government corporations and agencies |  |
ASSETS |  |
Debt securities, available-for-sale | 0 | 0
Fair Value Measurements, Recurring | Level 3 | Collateralized mortgage obligations of U.S. government corporations and agencies |  |
ASSETS |  |
Debt securities, available-for-sale | 0 | 0
Fair Value Measurements, Recurring | Level 3 | Residential mortgage-backed securities of U.S. government corporations and agencies |  |
ASSETS |  |
Debt securities, available-for-sale | 0 | 0
Fair Value Measurements, Recurring | Level 3 | Commercial mortgage-backed securities of U.S. government corporations and agencies |  |
ASSETS |  |
Debt securities, available-for-sale | 0 | 0
Fair Value Measurements, Recurring | Level 3 | Corporate obligations |  |
ASSETS |  |
Debt securities, available-for-sale | 0 | 0
Fair Value Measurements, Recurring | Level 3 | Obligations of states and political subdivisions |  |
ASSETS |  |
Debt securities, available-for-sale | 0 | 0
Fair Value Measurements, Recurring | Level 3 | Interest rate swaps |  |
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 | 2,900 | 0
Fair Value Measurements, Recurring | Level 3 | Forward sale contracts |  |
ASSETS |  |
Derivative financial assets |  | $ 0
LIABILITIES |  |
Derivative financial liabilities | $ 0 |

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