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Fair Value Measurements (Details 2) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Fair value measurements |  |
Investment securities available-for-sale | $ 1,197,467 | $ 1,040,583
Assets: |  |
Mortgages held for sale | 12,885 | 20,277
U.S. Treasury and Federal agencies securities |  |
Fair value measurements |  |
Investment securities available-for-sale | 619,482 | 526,964
U.S. States and political subdivisions securities |  |
Fair value measurements |  |
Investment securities available-for-sale | 81,127 | 84,505
Mortgage-backed securities - Federal agencies |  |
Fair value measurements |  |
Investment securities available-for-sale | 453,789 | 375,389
Corporate debt securities |  |
Fair value measurements |  |
Investment securities available-for-sale | 42,369 | 53,025
Foreign government and other securities |  |
Fair value measurements |  |
Investment securities available-for-sale | 700 | 700
Total |  |
Fair value measurements |  |
Investment securities available-for-sale | 1,197,467 | 1,040,583
Assets: |  |
Mortgages held for sale | 12,885 | 20,277
Level 1 |  |
Fair value measurements |  |
Investment securities available-for-sale | 80,285 | 80,393
Assets: |  |
Mortgages held for sale | 0 | 0
Level 2 |  |
Fair value measurements |  |
Investment securities available-for-sale | 1,115,030 | 957,898
Assets: |  |
Mortgages held for sale | 12,885 | 20,277
Level 3 |  |
Fair value measurements |  |
Investment securities available-for-sale | 2,152 | 2,292
Assets: |  |
Mortgages held for sale | 0 | 0
Recurring | Total |  |
Fair value measurements |  |
Investment securities available-for-sale | 1,197,467 | 1,040,583
Assets: |  |
Mortgages held for sale | 12,885 | 20,277
Total | 1,257,006 | 1,082,835
Liabilities: |  |
Total | 47,681 | 22,352
Recurring | Total | Interest rate swap contracts |  |
Assets: |  |
Accrued income and other assets | 46,654 | 21,975
Liabilities: |  |
Accrued expenses and other liabilities | 47,681 | 22,352
Recurring | Total | U.S. Treasury and Federal agencies securities |  |
Fair value measurements |  |
Investment securities available-for-sale | 619,482 | 526,964
Recurring | Total | U.S. States and political subdivisions securities |  |
Fair value measurements |  |
Investment securities available-for-sale | 81,127 | 84,505
Recurring | Total | Mortgage-backed securities - Federal agencies |  |
Fair value measurements |  |
Investment securities available-for-sale | 453,789 | 375,389
Recurring | Total | Corporate debt securities |  |
Fair value measurements |  |
Investment securities available-for-sale | 42,369 | 53,025
Recurring | Total | Foreign government and other securities |  |
Fair value measurements |  |
Investment securities available-for-sale | 700 | 700
Recurring | Level 1 |  |
Fair value measurements |  |
Investment securities available-for-sale | 80,285 | 80,393
Assets: |  |
Mortgages held for sale | 0 | 0
Total | 80,285 | 80,393
Liabilities: |  |
Total | 0 | 0
Recurring | Level 1 | Interest rate swap contracts |  |
Assets: |  |
Accrued income and other assets | 0 | 0
Liabilities: |  |
Accrued expenses and other liabilities | 0 | 0
Recurring | Level 1 | U.S. Treasury and Federal agencies securities |  |
Fair value measurements |  |
Investment securities available-for-sale | 80,285 | 80,393
Recurring | Level 1 | U.S. States and political subdivisions securities |  |
Fair value measurements |  |
Investment securities available-for-sale | 0 | 0
Recurring | Level 1 | Mortgage-backed securities - Federal agencies |  |
Fair value measurements |  |
Investment securities available-for-sale | 0 | 0
Recurring | Level 1 | Corporate debt securities |  |
Fair value measurements |  |
Investment securities available-for-sale | 0 | 0
Recurring | Level 1 | Foreign government and other securities |  |
Fair value measurements |  |
Investment securities available-for-sale | 0 | 0
Recurring | Level 2 |  |
Fair value measurements |  |
Investment securities available-for-sale | 1,115,030 | 957,898
Assets: |  |
Mortgages held for sale | 12,885 | 20,277
Total | 1,174,569 | 1,000,150
Liabilities: |  |
Total | 47,681 | 22,352
Recurring | Level 2 | Interest rate swap contracts |  |
Assets: |  |
Accrued income and other assets | 46,654 | 21,975
Liabilities: |  |
Accrued expenses and other liabilities | 47,681 | 22,352
Recurring | Level 2 | U.S. Treasury and Federal agencies securities |  |
Fair value measurements |  |
Investment securities available-for-sale | 539,197 | 446,571
Recurring | Level 2 | U.S. States and political subdivisions securities |  |
Fair value measurements |  |
Investment securities available-for-sale | 78,975 | 82,213
Recurring | Level 2 | Mortgage-backed securities - Federal agencies |  |
Fair value measurements |  |
Investment securities available-for-sale | 453,789 | 375,389
Recurring | Level 2 | Corporate debt securities |  |
Fair value measurements |  |
Investment securities available-for-sale | 42,369 | 53,025
Recurring | Level 2 | Foreign government and other securities |  |
Fair value measurements |  |
Investment securities available-for-sale | 700 | 700
Recurring | Level 3 |  |
Fair value measurements |  |
Investment securities available-for-sale | 2,152 | 2,292
Assets: |  |
Mortgages held for sale | 0 | 0
Total | 2,152 | 2,292
Liabilities: |  |
Total | 0 | 0
Recurring | Level 3 | Interest rate swap contracts |  |
Assets: |  |
Accrued income and other assets | 0 | 0
Liabilities: |  |
Accrued expenses and other liabilities | 0 | 0
Recurring | Level 3 | U.S. Treasury and Federal agencies securities |  |
Fair value measurements |  |
Investment securities available-for-sale | 0 | 0
Recurring | Level 3 | U.S. States and political subdivisions securities |  |
Fair value measurements |  |
Investment securities available-for-sale | 2,152 | 2,292
Recurring | Level 3 | Mortgage-backed securities - Federal agencies |  |
Fair value measurements |  |
Investment securities available-for-sale | 0 | 0
Recurring | Level 3 | Corporate debt securities |  |
Fair value measurements |  |
Investment securities available-for-sale | 0 | 0
Recurring | Level 3 | Foreign government and other securities |  |
Fair value measurements |  |
Investment securities available-for-sale | $ 0 | $ 0

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