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Fair Value Measurements - Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands | Sep. 30, 2021 | Dec. 31, 2020
--- | --- | ---
ASSETS |  |
Debt securities, available-for-sale, excluding accrued interest | $ 868,994 | $ 770,393
Marketable equity securities | 1,127 | 3,300
U.S. Treasury securities |  |
ASSETS |  |
Debt securities, available-for-sale, excluding accrued interest | 85,300 | 10,282
Obligations of U.S. government corporations and agencies |  |
ASSETS |  |
Debt securities, available-for-sale, excluding accrued interest | 71,205 | 82,904
Collateralized mortgage obligations of U.S. government corporations and agencies |  |
ASSETS |  |
Debt securities, available-for-sale, excluding accrued interest | 208,985 | 209,296
Residential mortgage-backed securities of U.S. government corporations and agencies |  |
ASSETS |  |
Debt securities, available-for-sale, excluding accrued interest | 60,442 | 67,778
Commercial mortgage-backed securities of U.S. government corporations and agencies |  |
ASSETS |  |
Debt securities, available-for-sale, excluding accrued interest | 356,506 | 273,681
Obligations of states and political subdivisions |  |
ASSETS |  |
Debt securities, available-for-sale, excluding accrued interest | 86,056 | 124,427
Fair Value Measurements, Recurring |  |
ASSETS |  |
Debt securities, available-for-sale, excluding accrued interest | 868,994 | 770,393
Marketable equity securities | 1,127 | 3,300
Total Securities | 870,121 | 773,693
Securities held in a deferred compensation plan | 9,320 | 6,794
Total Assets | 922,531 | 861,706
LIABILITIES |  |
Total Liabilities | 42,554 | 79,418
Fair Value Measurements, Recurring | U.S. Treasury securities |  |
ASSETS |  |
Debt securities, available-for-sale, excluding accrued interest | 85,300 | 10,282
Fair Value Measurements, Recurring | Obligations of U.S. government corporations and agencies |  |
ASSETS |  |
Debt securities, available-for-sale, excluding accrued interest | 71,205 | 82,904
Fair Value Measurements, Recurring | Collateralized mortgage obligations of U.S. government corporations and agencies |  |
ASSETS |  |
Debt securities, available-for-sale, excluding accrued interest | 208,985 | 209,296
Fair Value Measurements, Recurring | Residential mortgage-backed securities of U.S. government corporations and agencies |  |
ASSETS |  |
Debt securities, available-for-sale, excluding accrued interest | 60,442 | 67,778
Fair Value Measurements, Recurring | Commercial mortgage-backed securities of U.S. government corporations and agencies |  |
ASSETS |  |
Debt securities, available-for-sale, excluding accrued interest | 356,506 | 273,681
Fair Value Measurements, Recurring | Corporate obligations |  |
ASSETS |  |
Debt securities, available-for-sale, excluding accrued interest | 500 | 2,025
Fair Value Measurements, Recurring | Obligations of states and political subdivisions |  |
ASSETS |  |
Debt securities, available-for-sale, excluding accrued interest | 86,056 | 124,427
Fair Value Measurements, Recurring | Interest rate swaps |  |
ASSETS |  |
Derivative financial assets | 42,177 | 78,319
LIABILITIES |  |
Derivative financial liabilities | 42,554 | 79,033
Fair Value Measurements, Recurring | Interest rate lock commitments |  |
ASSETS |  |
Derivative financial assets | 812 | 2,900
Fair Value Measurements, Recurring | Forward sale contracts |  |
ASSETS |  |
Derivative financial assets | 101 |
LIABILITIES |  |
Derivative financial liabilities |  | 385
Fair Value Measurements, Recurring | Level 1 |  |
ASSETS |  |
Debt securities, available-for-sale, excluding accrued interest | 85,300 | 10,282
Marketable equity securities | 1,051 | 3,228
Total Securities | 86,351 | 13,510
Securities held in a deferred compensation plan | 9,320 | 6,794
Total Assets | 95,671 | 20,304
LIABILITIES |  |
Total Liabilities | 0 | 0
Fair Value Measurements, Recurring | Level 1 | U.S. Treasury securities |  |
ASSETS |  |
Debt securities, available-for-sale, excluding accrued interest | 85,300 | 10,282
Fair Value Measurements, Recurring | Level 1 | Obligations of U.S. government corporations and agencies |  |
ASSETS |  |
Debt securities, available-for-sale, excluding accrued interest | 0 | 0
Fair Value Measurements, Recurring | Level 1 | Collateralized mortgage obligations of U.S. government corporations and agencies |  |
ASSETS |  |
Debt securities, available-for-sale, excluding accrued interest | 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, excluding accrued interest | 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, excluding accrued interest | 0 | 0
Fair Value Measurements, Recurring | Level 1 | Corporate obligations |  |
ASSETS |  |
Debt securities, available-for-sale, excluding accrued interest | 0 | 0
Fair Value Measurements, Recurring | Level 1 | Obligations of states and political subdivisions |  |
ASSETS |  |
Debt securities, available-for-sale, excluding accrued interest | 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, excluding accrued interest | 783,694 | 760,111
Marketable equity securities | 76 | 72
Total Securities | 783,770 | 760,183
Securities held in a deferred compensation plan | 0 | 0
Total Assets | 825,947 | 838,502
LIABILITIES |  |
Total Liabilities | 42,554 | 79,418
Fair Value Measurements, Recurring | Level 2 | U.S. Treasury securities |  |
ASSETS |  |
Debt securities, available-for-sale, excluding accrued interest | 0 | 0
Fair Value Measurements, Recurring | Level 2 | Obligations of U.S. government corporations and agencies |  |
ASSETS |  |
Debt securities, available-for-sale, excluding accrued interest | 71,205 | 82,904
Fair Value Measurements, Recurring | Level 2 | Collateralized mortgage obligations of U.S. government corporations and agencies |  |
ASSETS |  |
Debt securities, available-for-sale, excluding accrued interest | 208,985 | 209,296
Fair Value Measurements, Recurring | Level 2 | Residential mortgage-backed securities of U.S. government corporations and agencies |  |
ASSETS |  |
Debt securities, available-for-sale, excluding accrued interest | 60,442 | 67,778
Fair Value Measurements, Recurring | Level 2 | Commercial mortgage-backed securities of U.S. government corporations and agencies |  |
ASSETS |  |
Debt securities, available-for-sale, excluding accrued interest | 356,506 | 273,681
Fair Value Measurements, Recurring | Level 2 | Corporate obligations |  |
ASSETS |  |
Debt securities, available-for-sale, excluding accrued interest | 500 | 2,025
Fair Value Measurements, Recurring | Level 2 | Obligations of states and political subdivisions |  |
ASSETS |  |
Debt securities, available-for-sale, excluding accrued interest | 86,056 | 124,427
Fair Value Measurements, Recurring | Level 2 | Interest rate swaps |  |
ASSETS |  |
Derivative financial assets | 42,177 | 78,319
LIABILITIES |  |
Derivative financial liabilities | 42,554 | 79,033
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 |  |
ASSETS |  |
Derivative financial assets | 0 |
LIABILITIES |  |
Derivative financial liabilities |  | 385
Fair Value Measurements, Recurring | Level 3 |  |
ASSETS |  |
Debt securities, available-for-sale, excluding accrued interest | 0 | 0
Marketable equity securities | 0 | 0
Total Securities | 0 | 0
Securities held in a deferred compensation plan | 0 | 0
Total Assets | 913 | 2,900
LIABILITIES |  |
Total Liabilities | 0 | 0
Fair Value Measurements, Recurring | Level 3 | U.S. Treasury securities |  |
ASSETS |  |
Debt securities, available-for-sale, excluding accrued interest | 0 | 0
Fair Value Measurements, Recurring | Level 3 | Obligations of U.S. government corporations and agencies |  |
ASSETS |  |
Debt securities, available-for-sale, excluding accrued interest | 0 | 0
Fair Value Measurements, Recurring | Level 3 | Collateralized mortgage obligations of U.S. government corporations and agencies |  |
ASSETS |  |
Debt securities, available-for-sale, excluding accrued interest | 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, excluding accrued interest | 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, excluding accrued interest | 0 | 0
Fair Value Measurements, Recurring | Level 3 | Corporate obligations |  |
ASSETS |  |
Debt securities, available-for-sale, excluding accrued interest | 0 | 0
Fair Value Measurements, Recurring | Level 3 | Obligations of states and political subdivisions |  |
ASSETS |  |
Debt securities, available-for-sale, excluding accrued interest | 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 | 812 | 2,900
Fair Value Measurements, Recurring | Level 3 | Forward sale contracts |  |
ASSETS |  |
Derivative financial assets | $ 101 |
LIABILITIES |  |
Derivative financial liabilities |  | $ 0

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