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Investment Securities (Details) - USD ($) $ in Thousands | Sep. 30, 2022 | Dec. 31, 2021
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Contractual maturities of investments in debt securities available-for-sale, Amortized Cost |  |
Due in one year or less | $ 85,315 |
Due after one year through five years | 1,118,538 |
Due after five years through ten years | 39,021 |
Due after ten years | 31,474 |
Mortgage-backed securities | 739,896 |
Total debt securities available-for-sale | 2,014,244 | $ 1,876,031
Contractual maturities of investments in debt securities available-for-sale, Fair Value |  |
Due in one year or less | 84,424 |
Due after one year through five years | 1,017,205 |
Due after five years through ten years | 32,807 |
Due after ten years | 29,068 |
Mortgage-backed securities | 637,690 |
Total debt securities available-for-sale | 1,801,194 | 1,863,041
Accrued interest receivable on investment securities available-for-sale | 5,300 | 4,800
U.S. Treasury and Federal agencies securities |  |
Contractual maturities of investments in debt securities available-for-sale, Amortized Cost |  |
Total debt securities available-for-sale | 1,131,244 | 1,093,780
Contractual maturities of investments in debt securities available-for-sale, Fair Value |  |
Total debt securities available-for-sale | 1,031,577 | 1,084,006
U.S. States and political subdivisions securities |  |
Contractual maturities of investments in debt securities available-for-sale, Amortized Cost |  |
Total debt securities available-for-sale | 126,008 | 95,700
Contractual maturities of investments in debt securities available-for-sale, Fair Value |  |
Total debt securities available-for-sale | 115,231 | 95,701
Mortgage-backed securities - Federal agencies |  |
Contractual maturities of investments in debt securities available-for-sale, Amortized Cost |  |
Total debt securities available-for-sale | 739,896 | 663,441
Contractual maturities of investments in debt securities available-for-sale, Fair Value |  |
Total debt securities available-for-sale | 637,690 | 659,727
Corporate debt securities |  |
Contractual maturities of investments in debt securities available-for-sale, Amortized Cost |  |
Total debt securities available-for-sale | 16,496 | 22,510
Contractual maturities of investments in debt securities available-for-sale, Fair Value |  |
Total debt securities available-for-sale | 16,113 | 23,009
Foreign government and other securities |  |
Contractual maturities of investments in debt securities available-for-sale, Amortized Cost |  |
Total debt securities available-for-sale | 600 | 600
Contractual maturities of investments in debt securities available-for-sale, Fair Value |  |
Total debt securities available-for-sale | $ 583 | $ 598

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